18408236 has 48 divisors (see below), whose sum is σ = 40884480. Its totient is φ = 7043520.

The previous prime is 18408233. The next prime is 18408281. The reversal of 18408236 is 63280481.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (18408233) 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 15 ways as a sum of consecutive naturals, for example, 17666 + ... + 18678.

It is an arithmetic number, because the mean of its divisors is an integer number (851760).

Almost surely, 2^18408236 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18408236, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20442240).

18408236 is an abundant number, since it is smaller than the sum of its proper divisors (22476244).

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

18408236 is a wasteful number, since it uses less digits than its factorization.

18408236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1094 (or 1092 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 32.

The square root of 18408236 is about 4290.4820242019. The cubic root of 18408236 is about 264.0406082315.

The spelling of 18408236 in words is "eighteen million, four hundred eight thousand, two hundred thirty-six".