18640746 has 32 divisors (see below), whose sum is σ = 42110400. Its totient is φ = 6110640.

The previous prime is 18640723. The next prime is 18640751. The reversal of 18640746 is 64704681.

18640746 is a `hidden beast` number, since 1 + 8 + 640 + 7 + 4 + 6 = 666.

It is a super-2 number, since 2×18640746² = 694954822873032, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18640746.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 465 + ... + 6123.

It is an arithmetic number, because the mean of its divisors is an integer number (1315950).

Almost surely, 2^18640746 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18640746, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21055200).

18640746 is an abundant number, since it is smaller than the sum of its proper divisors (23469654).

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

18640746 is a wasteful number, since it uses less digits than its factorization.

18640746 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5731 (or 5725 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 18640746 is about 4317.4930225769. The cubic root of 18640746 is about 265.1476381543.

The spelling of 18640746 in words is "eighteen million, six hundred forty thousand, seven hundred forty-six".