18201556808 has 12 divisors (see below), whose sum is σ = 34128634515. Its totient is φ = 9100587608.

The previous prime is 18201556757. The next prime is 18201556811. The reversal of 18201556808 is 80865510281.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in only one way, i.e., 9100778404 + 9100778404 = 95398^2 + 95398^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=95398.

It is a super-2 number, since 2×18201556808² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 357743 + ... + 405441.

Almost surely, 2^18201556808 is an apocalyptic number.

It is an amenable number.

18201556808 is a deficient number, since it is larger than the sum of its proper divisors (15927077707).

18201556808 is an frugal number, since it uses more digits than its factorization.

18201556808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95404 (or 47701 counting only the distinct ones).

The product of its (nonzero) digits is 153600, while the sum is 44.

The spelling of 18201556808 in words is "eighteen billion, two hundred one million, five hundred fifty-six thousand, eight hundred eight".