18444664 has 32 divisors (see below), whose sum is σ = 40089600. Its totient is φ = 7791840.

The previous prime is 18444661. The next prime is 18444703. The reversal of 18444664 is 46644481.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18444661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1657 + ... + 6295.

It is an arithmetic number, because the mean of its divisors is an integer number (1252800).

Almost surely, 2^18444664 is an apocalyptic number.

18444664 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18444664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20044800).

18444664 is an abundant number, since it is smaller than the sum of its proper divisors (21644936).

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

18444664 is a wasteful number, since it uses less digits than its factorization.

18444664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4723 (or 4719 counting only the distinct ones).

The product of its digits is 73728, while the sum is 37.

The square root of 18444664 is about 4294.7251367230. The cubic root of 18444664 is about 264.2146631778.

The spelling of 18444664 in words is "eighteen million, four hundred forty-four thousand, six hundred sixty-four".