18531768 has 64 divisors (see below), whose sum is σ = 50038560. Its totient is φ = 5697536.

The previous prime is 18531749. The next prime is 18531787. The reversal of 18531768 is 86713581.

It is an interprime number because it is at equal distance from previous prime (18531749) and next prime (18531787).

It is a congruent number.

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, 21196 + ... + 22052.

Almost surely, 2^18531768 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18531768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25019280).

18531768 is an abundant number, since it is smaller than the sum of its proper divisors (31506792).

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

18531768 is a wasteful number, since it uses less digits than its factorization.

18531768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 936 (or 932 counting only the distinct ones).

The product of its digits is 40320, while the sum is 39.

The square root of 18531768 is about 4304.8540044931. The cubic root of 18531768 is about 264.6299236752.

The spelling of 18531768 in words is "eighteen million, five hundred thirty-one thousand, seven hundred sixty-eight".