51921091044 has 45 divisors (see below), whose sum is σ = 135742711027. Its totient is φ = 17305663176.

The previous prime is 51921091009. The next prime is 51921091069. The reversal of 51921091044 is 44019012915.

It is a happy number.

The square root of 51921091044 is 227862.

It is a perfect power (a square), and thus also a powerful number.

51921091044 is a `hidden beast` number, since 519 + 2 + 10 + 91 + 0 + 44 = 666.

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

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 4095187 + ... + 4107845.

Almost surely, 2^51921091044 is an apocalyptic number.

51921091044 is a gapful number since it is divisible by the number (54) formed by its first and last digit.

51921091044 is the 227862-nd square number.

It is an amenable number.

51921091044 is an abundant number, since it is smaller than the sum of its proper divisors (83821619983).

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

51921091044 is an frugal number, since it uses more digits than its factorization.

51921091044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25334 (or 12664 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

Multiplying 51921091044 by its sum of digits (36), we get a square (1869159277584 = 1367172²).

51921091044 divided by its sum of digits (36) gives a square (1442252529 = 37977²).

The spelling of 51921091044 in words is "fifty-one billion, nine hundred twenty-one million, ninety-one thousand, forty-four".