18890638 has 32 divisors (see below), whose sum is σ = 32780160. Its totient is φ = 8087040.

The previous prime is 18890611. The next prime is 18890671. The reversal of 18890638 is 83609881.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 18890594 and 18890603.

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, 34648 + ... + 35188.

It is an arithmetic number, because the mean of its divisors is an integer number (1024380).

Almost surely, 2^18890638 is an apocalyptic number.

18890638 is a deficient number, since it is larger than the sum of its proper divisors (13889522).

18890638 is a wasteful number, since it uses less digits than its factorization.

18890638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 652.

The product of its (nonzero) digits is 82944, while the sum is 43.

The square root of 18890638 is about 4346.3361581912. The cubic root of 18890638 is about 266.3272114743.

The spelling of 18890638 in words is "eighteen million, eight hundred ninety thousand, six hundred thirty-eight".