18643679 has 12 divisors (see below), whose sum is σ = 20453568. Its totient is φ = 16972800.

The previous prime is 18643657. The next prime is 18643697. The reversal of 18643679 is 97634681.

It is not a de Polignac number, because 18643679 - 2⁸ = 18643423 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18643609) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7919 + ... + 9999.

It is an arithmetic number, because the mean of its divisors is an integer number (1704464).

Almost surely, 2^18643679 is an apocalyptic number.

18643679 is a deficient number, since it is larger than the sum of its proper divisors (1809889).

18643679 is a wasteful number, since it uses less digits than its factorization.

18643679 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2146 (or 2129 counting only the distinct ones).

The product of its digits is 217728, while the sum is 44.

The square root of 18643679 is about 4317.8326739233. The cubic root of 18643679 is about 265.1615438431.

The spelling of 18643679 in words is "eighteen million, six hundred forty-three thousand, six hundred seventy-nine".