51532491 has 16 divisors (see below), whose sum is σ = 72900000. Its totient is φ = 32268288.

The previous prime is 51532487. The next prime is 51532493. The reversal of 51532491 is 19423515.

It is not a de Polignac number, because 51532491 - 2² = 51532487 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51532493) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40635 + ... + 41883.

It is an arithmetic number, because the mean of its divisors is an integer number (4556250).

Almost surely, 2^51532491 is an apocalyptic number.

51532491 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

51532491 is a deficient number, since it is larger than the sum of its proper divisors (21367509).

51532491 is a wasteful number, since it uses less digits than its factorization.

51532491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2078.

The product of its digits is 5400, while the sum is 30.

The square root of 51532491 is about 7178.6134455060. The cubic root of 51532491 is about 372.1291680591.

The spelling of 51532491 in words is "fifty-one million, five hundred thirty-two thousand, four hundred ninety-one".