18136220 has 24 divisors (see below), whose sum is σ = 38169600. Its totient is φ = 7238592.

The previous prime is 18136211. The next prime is 18136243. The reversal of 18136220 is 2263181.

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, 13541 + ... + 14819.

It is an arithmetic number, because the mean of its divisors is an integer number (1590400).

Almost surely, 2^18136220 is an apocalyptic number.

18136220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18136220 is an abundant number, since it is smaller than the sum of its proper divisors (20033380).

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

18136220 is a wasteful number, since it uses less digits than its factorization.

18136220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1997 (or 1995 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 18136220 is about 4258.6641097884. The cubic root of 18136220 is about 262.7335849783.

The spelling of 18136220 in words is "eighteen million, one hundred thirty-six thousand, two hundred twenty".