51249231 has 24 divisors (see below), whose sum is σ = 83366400. Its totient is φ = 30056400.

The previous prime is 51249227. The next prime is 51249239. The reversal of 51249231 is 13294215.

It is not a de Polignac number, because 51249231 - 2² = 51249227 is a prime.

It is a super-2 number, since 2×51249231² = 5252967356182722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 51249195 and 51249204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51249239) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5281 + ... + 11418.

It is an arithmetic number, because the mean of its divisors is an integer number (3473600).

Almost surely, 2^51249231 is an apocalyptic number.

51249231 is a deficient number, since it is larger than the sum of its proper divisors (32117169).

51249231 is a wasteful number, since it uses less digits than its factorization.

51249231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16747 (or 16744 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

The square root of 51249231 is about 7158.8568221470. The cubic root of 51249231 is about 371.4460842193.

The spelling of 51249231 in words is "fifty-one million, two hundred forty-nine thousand, two hundred thirty-one".