51999925 has 6 divisors (see below), whose sum is σ = 64479938. Its totient is φ = 41599920.

The previous prime is 51999919. The next prime is 51999971. The reversal of 51999925 is 52999915.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 289444 + 51710481 = 538^2 + 7191^2 .

It is a de Polignac number, because none of the positive numbers 2^k-51999925 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1039974 + ... + 1040023.

Almost surely, 2^51999925 is an apocalyptic number.

It is an amenable number.

51999925 is a deficient number, since it is larger than the sum of its proper divisors (12480013).

51999925 is a wasteful number, since it uses less digits than its factorization.

51999925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2080007 (or 2080002 counting only the distinct ones).

The product of its digits is 328050, while the sum is 49.

The square root of 51999925 is about 7211.0973506118. The cubic root of 51999925 is about 373.2509362340.

The spelling of 51999925 in words is "fifty-one million, nine hundred ninety-nine thousand, nine hundred twenty-five".