18802640 has 40 divisors (see below), whose sum is σ = 44444328. Its totient is φ = 7395840.

The previous prime is 18802633. The next prime is 18802657. The reversal of 18802640 is 4620881.

It can be written as a sum of positive squares in 4 ways, for example, as 2383936 + 16418704 = 1544^2 + 4052^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2954 + ... + 6806.

Almost surely, 2^18802640 is an apocalyptic number.

18802640 is a gapful number since it is divisible by the number (10) 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 18802640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22222164).

18802640 is an abundant number, since it is smaller than the sum of its proper divisors (25641688).

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

18802640 is a wasteful number, since it uses less digits than its factorization.

18802640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3927 (or 3921 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 18802640 is about 4336.2011023475. The cubic root of 18802640 is about 265.9130248744.

The spelling of 18802640 in words is "eighteen million, eight hundred two thousand, six hundred forty".