18808638 has 8 divisors (see below), whose sum is σ = 37617288. Its totient is φ = 6269544.

The previous prime is 18808619. The next prime is 18808639. The reversal of 18808638 is 83680881.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

18808638 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 18808638.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18808639) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1567381 + ... + 1567392.

It is an arithmetic number, because the mean of its divisors is an integer number (4702161).

Almost surely, 2^18808638 is an apocalyptic number.

18808638 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

18808638 is a wasteful number, since it uses less digits than its factorization.

18808638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3134778.

The product of its (nonzero) digits is 73728, while the sum is 42.

The square root of 18808638 is about 4336.8926664145. The cubic root of 18808638 is about 265.9412970880.

The spelling of 18808638 in words is "eighteen million, eight hundred eight thousand, six hundred thirty-eight".