18156920 has 16 divisors (see below), whose sum is σ = 40853160. Its totient is φ = 7262752.

The previous prime is 18156911. The next prime is 18156923. The reversal of 18156920 is 2965181.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18156923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 226922 + ... + 227001.

Almost surely, 2^18156920 is an apocalyptic number.

18156920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18156920 is an abundant number, since it is smaller than the sum of its proper divisors (22696240).

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

18156920 is a wasteful number, since it uses less digits than its factorization.

18156920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 453934 (or 453930 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 18156920 is about 4261.0937563025. The cubic root of 18156920 is about 262.8335050533.

The spelling of 18156920 in words is "eighteen million, one hundred fifty-six thousand, nine hundred twenty".