51660231 has 16 divisors (see below), whose sum is σ = 82143744. Its totient is φ = 28236384.

The previous prime is 51660227. The next prime is 51660247. The reversal of 51660231 is 13206615.

It is not a de Polignac number, because 51660231 - 2² = 51660227 is a prime.

It is a super-2 number, since 2×51660231² = 5337558933946722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51660211) 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, 52996 + ... + 53961.

It is an arithmetic number, because the mean of its divisors is an integer number (5133984).

Almost surely, 2^51660231 is an apocalyptic number.

51660231 is a deficient number, since it is larger than the sum of its proper divisors (30483513).

51660231 is a wasteful number, since it uses less digits than its factorization.

51660231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106990.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 51660231 is about 7187.5051999981. The cubic root of 51660231 is about 372.4363953080.

Adding to 51660231 its reverse (13206615), we get a palindrome (64866846).

The spelling of 51660231 in words is "fifty-one million, six hundred sixty thousand, two hundred thirty-one".