23131530 has 24 divisors (see below), whose sum is σ = 60142212. Its totient is φ = 6168384.

The previous prime is 23131523. The next prime is 23131547. The reversal of 23131530 is 3513132.

23131530 is a `hidden beast` number, since 2 + 3 + 131 + 530 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 19793601 + 3337929 = 4449^2 + 1827^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 128419 + ... + 128598.

Almost surely, 2^23131530 is an apocalyptic number.

23131530 is an abundant number, since it is smaller than the sum of its proper divisors (37010682).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

23131530 is a wasteful number, since it uses less digits than its factorization.

23131530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257030 (or 257027 counting only the distinct ones).

The product of its (nonzero) digits is 270, while the sum is 18.

The square root of 23131530 is about 4809.5249245638. The cubic root of 23131530 is about 284.9277748653.

Adding to 23131530 its reverse (3513132), we get a palindrome (26644662).

The spelling of 23131530 in words is "twenty-three million, one hundred thirty-one thousand, five hundred thirty".