18918212 has 12 divisors (see below), whose sum is σ = 35054460. Its totient is φ = 8902656.

The previous prime is 18918199. The next prime is 18918233. The reversal of 18918212 is 21281981.

It can be written as a sum of positive squares in 2 ways, for example, as 9096256 + 9821956 = 3016^2 + 3134^2 .

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, 139037 + ... + 139172.

It is an arithmetic number, because the mean of its divisors is an integer number (2921205).

Almost surely, 2^18918212 is an apocalyptic number.

It is an amenable number.

18918212 is a deficient number, since it is larger than the sum of its proper divisors (16136248).

18918212 is a wasteful number, since it uses less digits than its factorization.

18918212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278230 (or 278228 counting only the distinct ones).

The product of its digits is 2304, while the sum is 32.

The square root of 18918212 is about 4349.5070985113. The cubic root of 18918212 is about 266.4567312979.

The spelling of 18918212 in words is "eighteen million, nine hundred eighteen thousand, two hundred twelve".