18475139 has 4 divisors (see below), whose sum is σ = 18516024. Its totient is φ = 18434256.

The previous prime is 18475129. The next prime is 18475151. The reversal of 18475139 is 93157481.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18475139 - 2¹² = 18471043 is a prime.

It is a super-2 number, since 2×18475139² = 682661522138642, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18475109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19757 + ... + 20670.

It is an arithmetic number, because the mean of its divisors is an integer number (4629006).

Almost surely, 2^18475139 is an apocalyptic number.

18475139 is a deficient number, since it is larger than the sum of its proper divisors (40885).

18475139 is an equidigital number, since it uses as much as digits as its factorization.

18475139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40884.

The product of its digits is 30240, while the sum is 38.

The square root of 18475139 is about 4298.2716293878. The cubic root of 18475139 is about 264.3600983987.

The spelling of 18475139 in words is "eighteen million, four hundred seventy-five thousand, one hundred thirty-nine".