51215825 has 12 divisors (see below), whose sum is σ = 66269568. Its totient is φ = 39190800.

The previous prime is 51215809. The next prime is 51215839. The reversal of 51215825 is 52851215.

It is not a de Polignac number, because 51215825 - 2⁴ = 51215809 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43961 + ... + 45110.

It is an arithmetic number, because the mean of its divisors is an integer number (5522464).

Almost surely, 2^51215825 is an apocalyptic number.

It is an amenable number.

51215825 is a deficient number, since it is larger than the sum of its proper divisors (15053743).

51215825 is a wasteful number, since it uses less digits than its factorization.

51215825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89104 (or 89099 counting only the distinct ones).

The product of its digits is 4000, while the sum is 29.

The square root of 51215825 is about 7156.5232480584. The cubic root of 51215825 is about 371.3653595937.

The spelling of 51215825 in words is "fifty-one million, two hundred fifteen thousand, eight hundred twenty-five".