18620639 has 8 divisors (see below), whose sum is σ = 20100960. Its totient is φ = 17196256.

The previous prime is 18620617. The next prime is 18620647. The reversal of 18620639 is 93602681.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18620639 - 2²⁴ = 1843423 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18620599 and 18620608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18620659) 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, 13292 + ... + 14625.

It is an arithmetic number, because the mean of its divisors is an integer number (2512620).

Almost surely, 2^18620639 is an apocalyptic number.

18620639 is a deficient number, since it is larger than the sum of its proper divisors (1480321).

18620639 is a wasteful number, since it uses less digits than its factorization.

18620639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27969.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 18620639 is about 4315.1638439345. The cubic root of 18620639 is about 265.0522692671.

The spelling of 18620639 in words is "eighteen million, six hundred twenty thousand, six hundred thirty-nine".