18204140 has 12 divisors (see below), whose sum is σ = 38228736. Its totient is φ = 7281648.

The previous prime is 18204133. The next prime is 18204143. The reversal of 18204140 is 4140281.

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 910207 = 18204140 / (1 + 8 + 2 + 0 + 4 + 1 + 4 + 0).

It is not an unprimeable number, because it can be changed into a prime (18204143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 455084 + ... + 455123.

It is an arithmetic number, because the mean of its divisors is an integer number (3185728).

Almost surely, 2^18204140 is an apocalyptic number.

18204140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18204140 is an abundant number, since it is smaller than the sum of its proper divisors (20024596).

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

18204140 is a wasteful number, since it uses less digits than its factorization.

18204140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 910216 (or 910214 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 18204140 is about 4266.6309894342. The cubic root of 18204140 is about 263.0611547995.

The spelling of 18204140 in words is "eighteen million, two hundred four thousand, one hundred forty".