18209139 has 16 divisors (see below), whose sum is σ = 26342400. Its totient is φ = 11121696.

The previous prime is 18209137. The next prime is 18209161. The reversal of 18209139 is 93190281.

It is not a de Polignac number, because 18209139 - 2¹ = 18209137 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18209137) 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, 3742 + ... + 7100.

It is an arithmetic number, because the mean of its divisors is an integer number (1646400).

Almost surely, 2^18209139 is an apocalyptic number.

18209139 is a deficient number, since it is larger than the sum of its proper divisors (8133261).

18209139 is a wasteful number, since it uses less digits than its factorization.

18209139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3514.

The product of its (nonzero) digits is 3888, while the sum is 33.

The square root of 18209139 is about 4267.2167744327. The cubic root of 18209139 is about 263.0852321496.

The spelling of 18209139 in words is "eighteen million, two hundred nine thousand, one hundred thirty-nine".