51115816800 has 144 divisors (see below), whose sum is σ = 184868948880. Its totient is φ = 13630878720.

The previous prime is 51115816727. The next prime is 51115816819. The reversal of 51115816800 is 861851115.

51115816800 is a `hidden beast` number, since 5 + 1 + 11 + 581 + 68 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×51115816800² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1161637 + ... + 1204836.

It is an arithmetic number, because the mean of its divisors is an integer number (1283812145).

Almost surely, 2^51115816800 is an apocalyptic number.

51115816800 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

51115816800 is an abundant number, since it is smaller than the sum of its proper divisors (133753132080).

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

51115816800 is a wasteful number, since it uses less digits than its factorization.

51115816800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2366502 (or 2366483 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 36.

The spelling of 51115816800 in words is "fifty-one billion, one hundred fifteen million, eight hundred sixteen thousand, eight hundred".