18113631 has 8 divisors (see below), whose sum is σ = 25422720. Its totient is φ = 11440152.

The previous prime is 18113611. The next prime is 18113647. The reversal of 18113631 is 13631181.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18113631 - 2⁷ = 18113503 is a prime.

It is a super-2 number, since 2×18113631² = 656207256008322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18113611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 158835 + ... + 158948.

It is an arithmetic number, because the mean of its divisors is an integer number (3177840).

Almost surely, 2^18113631 is an apocalyptic number.

18113631 is a deficient number, since it is larger than the sum of its proper divisors (7309089).

18113631 is a wasteful number, since it uses less digits than its factorization.

18113631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317805.

The product of its digits is 432, while the sum is 24.

The square root of 18113631 is about 4256.0111606997. The cubic root of 18113631 is about 262.6244598011.

The spelling of 18113631 in words is "eighteen million, one hundred thirteen thousand, six hundred thirty-one".