51981588 has 36 divisors (see below), whose sum is σ = 136267040. Its totient is φ = 17326872.

The previous prime is 51981583. The next prime is 51981613. The reversal of 51981588 is 88518915.

51981588 is a `hidden beast` number, since 519 + 81 + 58 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51981581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25768 + ... + 27711.

Almost surely, 2^51981588 is an apocalyptic number.

It is an amenable number.

51981588 is an abundant number, since it is smaller than the sum of its proper divisors (84285452).

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

51981588 is a wasteful number, since it uses less digits than its factorization.

51981588 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53498 (or 53484 counting only the distinct ones).

The product of its digits is 115200, while the sum is 45.

The square root of 51981588 is about 7209.8257953989. The cubic root of 51981588 is about 373.2070572791.

It can be divided in two parts, 5198 and 1588, that added together give a triangular number (6786 = T₁₁₆).

The spelling of 51981588 in words is "fifty-one million, nine hundred eighty-one thousand, five hundred eighty-eight".