18879638 has 16 divisors (see below), whose sum is σ = 29490480. Its totient is φ = 9053856.

The previous prime is 18879631. The next prime is 18879643. The reversal of 18879638 is 83697881.

It is a happy number.

It is a super-2 number, since 2×18879638² = 712881462022088, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18879631) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8456 + ... + 10452.

It is an arithmetic number, because the mean of its divisors is an integer number (1843155).

Almost surely, 2^18879638 is an apocalyptic number.

18879638 is a deficient number, since it is larger than the sum of its proper divisors (10610842).

18879638 is a wasteful number, since it uses less digits than its factorization.

18879638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2191.

The product of its digits is 580608, while the sum is 50.

The square root of 18879638 is about 4345.0705402789. The cubic root of 18879638 is about 266.2755074125.

The spelling of 18879638 in words is "eighteen million, eight hundred seventy-nine thousand, six hundred thirty-eight".