18397239 has 16 divisors (see below), whose sum is σ = 28182528. Its totient is φ = 10456992.

The previous prime is 18397237. The next prime is 18397261. The reversal of 18397239 is 93279381.

It is not a de Polignac number, because 18397239 - 2¹ = 18397237 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18397239.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18397231) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1914 + ... + 6360.

It is an arithmetic number, because the mean of its divisors is an integer number (1761408).

Almost surely, 2^18397239 is an apocalyptic number.

18397239 is a deficient number, since it is larger than the sum of its proper divisors (9785289).

18397239 is a wasteful number, since it uses less digits than its factorization.

18397239 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4654.

The product of its digits is 81648, while the sum is 42.

The square root of 18397239 is about 4289.2002751096. The cubic root of 18397239 is about 263.9880188548.

The spelling of 18397239 in words is "eighteen million, three hundred ninety-seven thousand, two hundred thirty-nine".