51520231 has 16 divisors (see below), whose sum is σ = 61024320. Its totient is φ = 42577920.

The previous prime is 51520219. The next prime is 51520247. The reversal of 51520231 is 13202515.

It is not a de Polignac number, because 51520231 - 2⁵ = 51520199 is a prime.

It is a super-2 number, since 2×51520231² = 5308668404586722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 51520199 and 51520208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51526231) 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, 24535 + ... + 26551.

It is an arithmetic number, because the mean of its divisors is an integer number (3814020).

Almost surely, 2^51520231 is an apocalyptic number.

51520231 is a deficient number, since it is larger than the sum of its proper divisors (9504089).

51520231 is a wasteful number, since it uses less digits than its factorization.

51520231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2154.

The product of its (nonzero) digits is 300, while the sum is 19.

The square root of 51520231 is about 7177.7594693609. The cubic root of 51520231 is about 372.0996548635.

Adding to 51520231 its reverse (13202515), we get a palindrome (64722746).

The spelling of 51520231 in words is "fifty-one million, five hundred twenty thousand, two hundred thirty-one".