18956220 has 24 divisors (see below), whose sum is σ = 53077584. Its totient is φ = 5054976.

The previous prime is 18956191. The next prime is 18956237. The reversal of 18956220 is 2265981.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 157909 + ... + 158028.

It is an arithmetic number, because the mean of its divisors is an integer number (2211566).

Almost surely, 2^18956220 is an apocalyptic number.

18956220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18956220 is an abundant number, since it is smaller than the sum of its proper divisors (34121364).

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

18956220 is a wasteful number, since it uses less digits than its factorization.

18956220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 315949 (or 315947 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 18956220 is about 4353.8741369038. The cubic root of 18956220 is about 266.6350552806.

The spelling of 18956220 in words is "eighteen million, nine hundred fifty-six thousand, two hundred twenty".