18918520 has 16 divisors (see below), whose sum is σ = 42566760. Its totient is φ = 7567392.

The previous prime is 18918517. The next prime is 18918539. The reversal of 18918520 is 2581981.

It is a congruent number.

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, 236442 + ... + 236521.

Almost surely, 2^18918520 is an apocalyptic number.

18918520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18918520 is an abundant number, since it is smaller than the sum of its proper divisors (23648240).

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

18918520 is a wasteful number, since it uses less digits than its factorization.

18918520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 472974 (or 472970 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 34.

The square root of 18918520 is about 4349.5425046779. The cubic root of 18918520 is about 266.4581773160.

The spelling of 18918520 in words is "eighteen million, nine hundred eighteen thousand, five hundred twenty".