51125664 has 48 divisors (see below), whose sum is σ = 142103808. Its totient is φ = 16038912.

The previous prime is 51125639. The next prime is 51125671. The reversal of 51125664 is 46652115.

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×51125664² = 5227667038881792, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14032 + ... + 17295.

It is an arithmetic number, because the mean of its divisors is an integer number (2960496).

Almost surely, 2^51125664 is an apocalyptic number.

It is an amenable number.

51125664 is an abundant number, since it is smaller than the sum of its proper divisors (90978144).

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

51125664 is a wasteful number, since it uses less digits than its factorization.

51125664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31357 (or 31349 counting only the distinct ones).

The product of its digits is 7200, while the sum is 30.

The square root of 51125664 is about 7150.2212553179. The cubic root of 51125664 is about 371.1473128005.

Adding to 51125664 its reverse (46652115), we get a palindrome (97777779).

The spelling of 51125664 in words is "fifty-one million, one hundred twenty-five thousand, six hundred sixty-four".