18520540072 has 16 divisors (see below), whose sum is σ = 34729348500. Its totient is φ = 9259380480.

The previous prime is 18520540063. The next prime is 18520540099. The reversal of 18520540072 is 27004502581.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 12491638756 + 6028901316 = 111766^2 + 77646^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18129 + ... + 193312.

Almost surely, 2^18520540072 is an apocalyptic number.

It is an amenable number.

18520540072 is a deficient number, since it is larger than the sum of its proper divisors (16208808428).

18520540072 is a wasteful number, since it uses less digits than its factorization.

18520540072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222396 (or 222392 counting only the distinct ones).

The product of its (nonzero) digits is 22400, while the sum is 34.

The spelling of 18520540072 in words is "eighteen billion, five hundred twenty million, five hundred forty thousand, seventy-two".