51239172 has 48 divisors (see below), whose sum is σ = 124871040. Its totient is φ = 16332288.

The previous prime is 51239141. The next prime is 51239189. The reversal of 51239172 is 27193215.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

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 15 ways as a sum of consecutive naturals, for example, 38673 + ... + 39975.

It is an arithmetic number, because the mean of its divisors is an integer number (2601480).

Almost surely, 2^51239172 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 51239172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (62435520).

51239172 is an abundant number, since it is smaller than the sum of its proper divisors (73631868).

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

51239172 is a wasteful number, since it uses less digits than its factorization.

51239172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1452 (or 1450 counting only the distinct ones).

The product of its digits is 3780, while the sum is 30.

The square root of 51239172 is about 7158.1542313644. The cubic root of 51239172 is about 371.4217806310.

The spelling of 51239172 in words is "fifty-one million, two hundred thirty-nine thousand, one hundred seventy-two".