18118640 has 20 divisors (see below), whose sum is σ = 42126024. Its totient is φ = 7247424.

The previous prime is 18118603. The next prime is 18118657. The reversal of 18118640 is 4681181.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

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, 113162 + ... + 113321.

Almost surely, 2^18118640 is an apocalyptic number.

18118640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18118640 is an abundant number, since it is smaller than the sum of its proper divisors (24007384).

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

18118640 is a wasteful number, since it uses less digits than its factorization.

18118640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226496 (or 226490 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 29.

The square root of 18118640 is about 4256.5995818258. The cubic root of 18118640 is about 262.6486655991.

The spelling of 18118640 in words is "eighteen million, one hundred eighteen thousand, six hundred forty".