18861432668 has 24 divisors (see below), whose sum is σ = 35563451280. Its totient is φ = 8701136640.

The previous prime is 18861432659. The next prime is 18861432671. The reversal of 18861432668 is 86623416881.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25523 + ... + 195893.

It is an arithmetic number, because the mean of its divisors is an integer number (1481810470).

Almost surely, 2^18861432668 is an apocalyptic number.

It is an amenable number.

18861432668 is a deficient number, since it is larger than the sum of its proper divisors (16702018612).

18861432668 is a wasteful number, since it uses less digits than its factorization.

18861432668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172517 (or 172515 counting only the distinct ones).

The product of its digits is 2654208, while the sum is 53.

The spelling of 18861432668 in words is "eighteen billion, eight hundred sixty-one million, four hundred thirty-two thousand, six hundred sixty-eight".