51931872 has 72 divisors (see below), whose sum is σ = 156383136. Its totient is φ = 16290816.

The previous prime is 51931843. The next prime is 51931903. The reversal of 51931872 is 27813915.

It is a tau number, because it is divible by the number of its divisors (72).

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 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, 408 + ... + 10199.

It is an arithmetic number, because the mean of its divisors is an integer number (2171988).

Almost surely, 2^51931872 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51931872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78191568).

51931872 is an abundant number, since it is smaller than the sum of its proper divisors (104451264).

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

51931872 is a wasteful number, since it uses less digits than its factorization.

51931872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10640 (or 10629 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 51931872 is about 7206.3771758075. The cubic root of 51931872 is about 373.0880389809.

The spelling of 51931872 in words is "fifty-one million, nine hundred thirty-one thousand, eight hundred seventy-two".