51901921944 has 48 divisors (see below), whose sum is σ = 148836397320. Its totient is φ = 16282955520.

The previous prime is 51901921943. The next prime is 51901921997. The reversal of 51901921944 is 44912910915.

51901921944 is a `hidden beast` number, since 519 + 0 + 1 + 92 + 1 + 9 + 44 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 51901921944.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51901921943) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21200542 + ... + 21202989.

Almost surely, 2^51901921944 is an apocalyptic number.

It is an amenable number.

51901921944 is an abundant number, since it is smaller than the sum of its proper divisors (96934475376).

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

51901921944 is a wasteful number, since it uses less digits than its factorization.

51901921944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42403560 (or 42403553 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 45.

The spelling of 51901921944 in words is "fifty-one billion, nine hundred one million, nine hundred twenty-one thousand, nine hundred forty-four".