800 (number)

This article is about the number. For the year, see 800. For other uses, see 800 (disambiguation).
799 800 801
Cardinal eight hundred
Ordinal 800th
(eight hundredth)
Factorization 25× 52
Roman numeral DCCC
Binary 11001000002
Ternary 10021223
Quaternary 302004
Quinary 112005
Senary 34126
Octal 14408
Duodecimal 56812
Hexadecimal 32016
Vigesimal 20020
Base 36 M836

800 (eight hundred) is the natural number following 799 and preceding 801.

It is the sum of four consecutive primes (193 + 197 + 199 + 211). It is a Harshad number.


801 = 32 × 89, Harshad number


802 = 2 × 401, sum of eight consecutive primes (83 + 89 + 97 + 101 + 103 + 107 + 109 + 113), nontotient, happy number


803 = 11 × 73, sum of three consecutive primes (263 + 269 + 271), sum of nine consecutive primes (71 + 73 + 79 + 83 + 89 + 97 + 101 + 103 + 107), Harshad number


804 = 22 × 3 × 67, nontotient, Harshad number


805 = 5 × 7 × 23


806 = 2 × 13 × 31, sphenic number, nontotient, totient sum for first 51 integers, happy number


807 = 3 × 269


808 = 23 × 101, strobogrammatic number


809 prime number, Sophie Germain prime, Chen prime, Eisenstein prime with no imaginary part


810 = 2 × 34 × 5, Harshad number


811 prime number, sum of five consecutive primes (151 + 157 + 163 + 167 + 173), Chen prime, happy number, the Mertens function of 811 returns 0


812 = 22 × 7 × 29, pronic number, the Mertens function of 812 returns 0


813 = 3 × 271


814 = 2 × 11 × 37, sphenic number, the Mertens function of 814 returns 0, nontotient


815 = 5 × 163


816 = 24 × 3 × 17, tetrahedral number, Padovan number, Zuckerman number


817 = 19 × 43, sum of three consecutive primes (269 + 271 + 277), centered hexagonal number


818 = 2 × 409, nontotient, strobogrammatic number


819 = 32 × 7 × 13, square pyramidal number


820 = 22 × 5 × 41, triangular number, Harshad number, happy number, repdigit (1111) in base 9


821 prime number, twin prime, Eisenstein prime with no imaginary part, prime quadruplet with 823, 827, 829


822 = 2 × 3 × 137, sum of twelve consecutive primes (43 + 47 + 53 + 59 + 61 + 67 + 71 + 73 + 79 + 83 + 89 + 97), sphenic number, member of the Mian–Chowla sequence


823 prime number, twin prime, the Mertens function of 823 returns 0, prime quadruplet with 821, 827, 829


824 = 23 × 103, sum of ten consecutive primes (61 + 67 + 71 + 73 + 79 + 83 + 89 + 97 + 101 + 103), the Mertens function of 824 returns 0, nontotient


825 = 3 × 52 × 11, Smith number, the Mertens function 825 returns 0, Harshad number


826 = 2 × 7 × 59, sphenic number


827 prime number, twin prime, part of prime quadruplet with {821, 823, 829}, sum of seven consecutive primes (103 + 107 + 109 + 113 + 127 + 131 + 137), Chen prime, Eisenstein prime with no imaginary part, strictly non-palindromic number


828 = 22 × 32 × 23, Harshad number


829 prime number, twin prime, part of prime quadruplet with {827, 823, 821}, sum of three consecutive primes (271 + 277 + 281), Chen prime


830 = 2 × 5 × 83, sphenic number, sum of four consecutive primes (197 + 199 + 211 + 223), nontotient, totient sum for first 52 integers


831 = 3 × 277


832 = 26 × 13, Harshad number


833 = 72 × 17


834 = 2 × 3 × 139, sphenic number, sum of six consecutive primes (127 + 131 + 137 + 139 + 149 + 151), nontotient


835 = 5 × 167, Motzkin number


836 = 22 × 11 × 19, weird number


837 = 33 × 31


838 = 2 × 419


839 prime number, safe prime, sum of five consecutive primes (157 + 163 + 167 + 173 + 179), Chen prime, Eisenstein prime with no imaginary part, highly cototient number


840 = 23 × 3 × 5 × 7, highly composite number, smallest numbers divisible by the numbers 1 to 8 (lowest common multiple of 1 to 8), sparsely totient number, Harshad number in base 2 through base 10


841 = 292 = 202 + 212, sum of three consecutive primes (277 + 281 + 283), sum of nine consecutive primes (73 + 79 + 83 + 89 + 97 + 101 + 103 + 107 + 109), centered square number, centered heptagonal number, centered octagonal number


842 = 2 × 421, nontotient


843 = 3 × 281, Lucas number


844 = 22 × 211, nontotient


845 = 5 × 132


846 = 2 × 32 × 47, sum of eight consecutive primes (89 + 97 + 101 + 103 + 107 + 109 + 113 + 127), nontotient, Harshad number


847 = 7 × 112, happy number


848 = 24 × 53


849 = 3 × 283, the Mertens function of 849 returns 0


850 = 2 × 52 × 17, the Mertens function 850 returns 0, nontotient, the maximum possible Fair Isaac credit score, country calling code for North Korea


851 = 23 × 37


852 = 22 × 3 × 71, pentagonal number, Smith number


853 prime number, Perrin number, the Mertens function of 853 returns 0, average of first 853 prime numbers is an integer (sequence A045345 in OEIS), strictly non-palindromic number, number of connected graphs with 7 nodes


854 = 2 × 7 × 61, nontotient


855 = 32 × 5 × 19, decagonal number, centered cube number


856 = 23 × 107, nonagonal number, centered pentagonal number, happy number


857 prime number, sum of three consecutive primes (281 + 283 + 293), Chen prime, Eisenstein prime with no imaginary part


858 = 2 × 3 × 11 × 13, Giuga number


859 prime number


860 = 22 × 5 × 43, sum of four consecutive primes (199 + 211 + 223 + 227)


861 = 3 × 7 × 41, sphenic number, triangular number, hexagonal number, Smith number


862 = 2 × 431


863 prime number, safe prime, sum of five consecutive primes (163 + 167 + 173 + 179 + 181), sum of seven consecutive primes (107 + 109 + 113 + 127 + 131 + 137 + 139), Chen prime, Eisenstein prime with no imaginary part


864 = 25 × 33, sum of a twin prime (431 + 433), sum of six consecutive primes (131 + 137 + 139 + 149 + 151 + 157), Harshad number


865 = 5 × 173,


866 = 2 × 433, nontotient


867 = 3 × 172


868 = 22 × 7 × 31, nontotient


869 = 11 × 79, the Mertens function 869 returns 0


870 = 2 × 3 × 5 × 29, sum of ten consecutive primes (67 + 71 + 73 + 79 + 83 + 89 + 97 + 101 + 103 + 107), pronic number, nontotient, sparsely totient number, Harshad number

This number is the magic constant of n×n normal magic square and n-queens problem for n = 12.


871 = 13 × 67


872 = 23 × 109, nontotient


873 = 32 × 97, sum of the first six factorials from 1


874 = 2 × 19 × 23, sum of the first twenty-three primes, sum of the first seven factorials from 0, nontotient, Harshad number, happy number


875 = 53 × 7


876 = 22 × 3 × 73


877 prime number, Bell number, Chen prime, the Mertens function of 877 returns 0, strictly non-palindromic number.


878 = 2 × 439, nontotient


879 = 3 × 293


880 = 24 × 5 × 11, Harshad number; 148-gonal number; the number of n×n magic squares for n = 4.


881 prime number, twin prime, sum of nine consecutive primes (79 + 83 + 89 + 97 + 101 + 103 + 107 + 109 + 113), Chen prime, Eisenstein prime with no imaginary part


882 = 2 × 32 × 72, Harshad number, totient sum for first 53 integers


883 prime number, twin prime, sum of three consecutive primes (283 + 293 + 307), the Mertens function of 883 returns 0, happy number


884 = 22 × 13 × 17, the Mertens function 884 returns 0


885 = 3 × 5 × 59, sphenic number


886 = 2 × 443, the Mertens function of 886 returns 0


887 prime number followed by primal gap of 20, safe prime, Chen prime, Eisenstein prime with no imaginary part


888 = 23 × 3 × 37, sum of eight consecutive primes (97 + 101 + 103 + 107 + 109 + 113 + 127 + 131), Harshad number.


889 = 7 × 127, the Mertens function of 889 returns 0


890 = 2 × 5 × 89, sphenic number, sum of four consecutive primes (211 + 223 + 227 + 229), nontotient


891 = 34 × 11, sum of five consecutive primes (167 + 173 + 179 + 181 + 191), octahedral number


892 = 22 × 223, nontotient


893 = 19 × 47, the Mertens function 893 returns 0


894 = 2 × 3 × 149, sphenic number, nontotient


895 = 5 × 179, Smith number, Woodall number, the Mertens function 895 returns 0


896 = 27 × 7, sum of six consecutive primes (137 + 139 + 149 + 151 + 157 + 163), the Mertens function 896 returns 0


897 = 3 × 13 × 23, sphenic number


898 = 2 × 449, the Mertens function of 898 returns 0, nontotient


899 = 29 × 31, happy number