23515231 has 4 divisors (see below), whose sum is σ = 23531472. Its totient is φ = 23498992.

The previous prime is 23515213. The next prime is 23515249. The reversal of 23515231 is 13251532.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (23515213) and next prime (23515249).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23515231 is a prime.

It is a super-2 number, since 2×23515231² = 1105932177966722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23515211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5710 + ... + 8923.

It is an arithmetic number, because the mean of its divisors is an integer number (5882868).

Almost surely, 2^23515231 is an apocalyptic number.

23515231 is a deficient number, since it is larger than the sum of its proper divisors (16241).

23515231 is a wasteful number, since it uses less digits than its factorization.

23515231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16240.

The product of its digits is 900, while the sum is 22.

The square root of 23515231 is about 4849.2505606537. The cubic root of 23515231 is about 286.4945840901.

Adding to 23515231 its reverse (13251532), we get a palindrome (36766763).

The spelling of 23515231 in words is "twenty-three million, five hundred fifteen thousand, two hundred thirty-one".