18316644 has 12 divisors (see below), whose sum is σ = 42738864. Its totient is φ = 6105544.

The previous prime is 18316643. The next prime is 18316673. The reversal of 18316644 is 44661381.

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

It is not an unprimeable number, because it can be changed into a prime (18316643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 763182 + ... + 763205.

It is an arithmetic number, because the mean of its divisors is an integer number (3561572).

Almost surely, 2^18316644 is an apocalyptic number.

It is an amenable number.

18316644 is an abundant number, since it is smaller than the sum of its proper divisors (24422220).

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

18316644 is a wasteful number, since it uses less digits than its factorization.

18316644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1526394 (or 1526392 counting only the distinct ones).

The product of its digits is 13824, while the sum is 33.

The square root of 18316644 is about 4279.7948548967. The cubic root of 18316644 is about 263.6019598532.

The spelling of 18316644 in words is "eighteen million, three hundred sixteen thousand, six hundred forty-four".