51239331 has 64 divisors (see below), whose sum is σ = 93219840. Its totient is φ = 27371520.

The previous prime is 51239327. The next prime is 51239341. The reversal of 51239331 is 13393215.

It is a happy number.

It is not a de Polignac number, because 51239331 - 2² = 51239327 is a prime.

It is a super-2 number, since 2×51239331² = 5250938082655122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 51239295 and 51239304.

It is not an unprimeable number, because it can be changed into a prime (51239341) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 88515 + ... + 89091.

It is an arithmetic number, because the mean of its divisors is an integer number (1456560).

Almost surely, 2^51239331 is an apocalyptic number.

51239331 is a deficient number, since it is larger than the sum of its proper divisors (41980509).

51239331 is a wasteful number, since it uses less digits than its factorization.

51239331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 633 (or 627 counting only the distinct ones).

The product of its digits is 2430, while the sum is 27.

The square root of 51239331 is about 7158.1653375708. The cubic root of 51239331 is about 371.4221648162.

The spelling of 51239331 in words is "fifty-one million, two hundred thirty-nine thousand, three hundred thirty-one".