18902640 has 160 divisors (see below), whose sum is σ = 64120896. Its totient is φ = 4587520.

The previous prime is 18902629. The next prime is 18902641. The reversal of 18902640 is 4620981.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 18902598 and 18902607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18902641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 167224 + ... + 167336.

Almost surely, 2^18902640 is an apocalyptic number.

18902640 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 18902640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32060448).

18902640 is an abundant number, since it is smaller than the sum of its proper divisors (45218256).

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

18902640 is a wasteful number, since it uses less digits than its factorization.

18902640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187 (or 181 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 18902640 is about 4347.7166421008. The cubic root of 18902640 is about 266.3836024140.

The spelling of 18902640 in words is "eighteen million, nine hundred two thousand, six hundred forty".