18938156 has 12 divisors (see below), whose sum is σ = 33289368. Its totient is φ = 9426912.

The previous prime is 18938149. The next prime is 18938159. The reversal of 18938156 is 65183981.

It is not an unprimeable number, because it can be changed into a prime (18938159) 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, 9521 + ... + 11336.

It is an arithmetic number, because the mean of its divisors is an integer number (2774114).

Almost surely, 2^18938156 is an apocalyptic number.

It is an amenable number.

18938156 is a deficient number, since it is larger than the sum of its proper divisors (14351212).

18938156 is a wasteful number, since it uses less digits than its factorization.

18938156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21088 (or 21086 counting only the distinct ones).

The product of its digits is 51840, while the sum is 41.

The square root of 18938156 is about 4351.7991681602. The cubic root of 18938156 is about 266.5503332847.

The spelling of 18938156 in words is "eighteen million, nine hundred thirty-eight thousand, one hundred fifty-six".