18539094631 has 4 divisors (see below), whose sum is σ = 18540696672. Its totient is φ = 18537492592.

The previous prime is 18539094617. The next prime is 18539094647. The reversal of 18539094631 is 13649093581.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18539094631 is a prime.

It is a super-2 number, since 2×18539094631² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18539094601) 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, 783535 + ... + 806848.

It is an arithmetic number, because the mean of its divisors is an integer number (4635174168).

Almost surely, 2^18539094631 is an apocalyptic number.

18539094631 is a deficient number, since it is larger than the sum of its proper divisors (1602041).

18539094631 is a wasteful number, since it uses less digits than its factorization.

18539094631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1602040.

The product of its (nonzero) digits is 699840, while the sum is 49.

The spelling of 18539094631 in words is "eighteen billion, five hundred thirty-nine million, ninety-four thousand, six hundred thirty-one".