18700644 has 12 divisors (see below), whose sum is σ = 43634864. Its totient is φ = 6233544.

The previous prime is 18700631. The next prime is 18700673. The reversal of 18700644 is 44600781.

It is a tau number, because it is divible by the number of its divisors (12).

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, 779182 + ... + 779205.

Almost surely, 2^18700644 is an apocalyptic number.

It is an amenable number.

18700644 is an abundant number, since it is smaller than the sum of its proper divisors (24934220).

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

18700644 is a wasteful number, since it uses less digits than its factorization.

18700644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1558394 (or 1558392 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 18700644 is about 4324.4241235106. The cubic root of 18700644 is about 265.4313326768.

The spelling of 18700644 in words is "eighteen million, seven hundred thousand, six hundred forty-four".