51431363856 has 80 divisors (see below), whose sum is σ = 147900613120. Its totient is φ = 17112021120.

The previous prime is 51431363827. The next prime is 51431363927. The reversal of 51431363856 is 65836313415.

51431363856 is a `hidden beast` number, since 5 + 1 + 4 + 3 + 1 + 3 + 638 + 5 + 6 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 123681 + ... + 343743.

It is an arithmetic number, because the mean of its divisors is an integer number (1848757664).

Almost surely, 2^51431363856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51431363856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73950306560).

51431363856 is an abundant number, since it is smaller than the sum of its proper divisors (96469249264).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51431363856 is a wasteful number, since it uses less digits than its factorization.

51431363856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220621 (or 220609 counting only the distinct ones).

The product of its digits is 777600, while the sum is 45.

The spelling of 51431363856 in words is "fifty-one billion, four hundred thirty-one million, three hundred sixty-three thousand, eight hundred fifty-six".