51289531 has 18 divisors (see below), whose sum is σ = 56859180. Its totient is φ = 46135440.

The previous prime is 51289523. The next prime is 51289547. The reversal of 51289531 is 13598215.

It is not a de Polignac number, because 51289531 - 2³ = 51289523 is a prime.

It is a super-2 number, since 2×51289531² = 5261231980399922, which contains 22 as substring.

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51289501) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 967701 + ... + 967753.

Almost surely, 2^51289531 is an apocalyptic number.

51289531 is a deficient number, since it is larger than the sum of its proper divisors (5569649).

51289531 is an equidigital number, since it uses as much as digits as its factorization.

51289531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187 (or 103 counting only the distinct ones).

The product of its digits is 10800, while the sum is 34.

The square root of 51289531 is about 7161.6709642373. The cubic root of 51289531 is about 371.5434213234.

The spelling of 51289531 in words is "fifty-one million, two hundred eighty-nine thousand, five hundred thirty-one".