18664839 has 12 divisors (see below), whose sum is σ = 27013896. Its totient is φ = 12418512.

The previous prime is 18664831. The next prime is 18664843. The reversal of 18664839 is 93846681.

It is not a de Polignac number, because 18664839 - 2³ = 18664831 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18664794 and 18664803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18664831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3517 + ... + 7049.

It is an arithmetic number, because the mean of its divisors is an integer number (2251158).

Almost surely, 2^18664839 is an apocalyptic number.

18664839 is a deficient number, since it is larger than the sum of its proper divisors (8349057).

18664839 is a wasteful number, since it uses less digits than its factorization.

18664839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4126 (or 4123 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 18664839 is about 4320.2822824441. The cubic root of 18664839 is about 265.2618226364.

It can be divided in two parts, 18664 and 839, that added together give a triangular number (19503 = T₁₉₇).

The spelling of 18664839 in words is "eighteen million, six hundred sixty-four thousand, eight hundred thirty-nine".