18979668 has 36 divisors (see below), whose sum is σ = 49276500. Its totient is φ = 6155136.

The previous prime is 18979663. The next prime is 18979687. The reversal of 18979668 is 86697981.

It can be written as a sum of positive squares in 2 ways, for example, as 15586704 + 3392964 = 3948^2 + 1842^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18979663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5793 + ... + 8456.

Almost surely, 2^18979668 is an apocalyptic number.

18979668 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

18979668 is an abundant number, since it is smaller than the sum of its proper divisors (30296832).

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

18979668 is a wasteful number, since it uses less digits than its factorization.

18979668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14296 (or 14291 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 54.

The square root of 18979668 is about 4356.5660789204. The cubic root of 18979668 is about 266.7449485453.

The spelling of 18979668 in words is "eighteen million, nine hundred seventy-nine thousand, six hundred sixty-eight".