18818517408 has 24 divisors (see below), whose sum is σ = 49398608448. Its totient is φ = 6272839104.

The previous prime is 18818517391. The next prime is 18818517413. The reversal of 18818517408 is 80471581881.

It is a tau number, because it is divible by the number of its divisors (24).

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, 98013016 + ... + 98013207.

It is an arithmetic number, because the mean of its divisors is an integer number (2058275352).

Almost surely, 2^18818517408 is an apocalyptic number.

It is an amenable number.

18818517408 is an abundant number, since it is smaller than the sum of its proper divisors (30580091040).

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

18818517408 is a wasteful number, since it uses less digits than its factorization.

18818517408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196026236 (or 196026228 counting only the distinct ones).

The product of its (nonzero) digits is 573440, while the sum is 51.

The spelling of 18818517408 in words is "eighteen billion, eight hundred eighteen million, five hundred seventeen thousand, four hundred eight".