51687217044 has 192 divisors, whose sum is σ = 146071537920. Its totient is φ = 15739453440.

The previous prime is 51687217039. The next prime is 51687217063. The reversal of 51687217044 is 44071278615.

51687217044 is a `hidden beast` number, since 516 + 8 + 7 + 21 + 70 + 44 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 43543819 + ... + 43545005.

It is an arithmetic number, because the mean of its divisors is an integer number (760789260).

Almost surely, 2^51687217044 is an apocalyptic number.

51687217044 is a gapful number since it is divisible by the number (54) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51687217044, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73035768960).

51687217044 is an abundant number, since it is smaller than the sum of its proper divisors (94384320876).

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

51687217044 is a wasteful number, since it uses less digits than its factorization.

51687217044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1895 (or 1887 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 45.

The spelling of 51687217044 in words is "fifty-one billion, six hundred eighty-seven million, two hundred seventeen thousand, forty-four".