18139294 has 4 divisors (see below), whose sum is σ = 27208944. Its totient is φ = 9069646.

The previous prime is 18139279. The next prime is 18139307. The reversal of 18139294 is 49293181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 49293181 = 7 ⋅7041883.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 4534822 + ... + 4534825.

It is an arithmetic number, because the mean of its divisors is an integer number (6802236).

Almost surely, 2^18139294 is an apocalyptic number.

18139294 is a deficient number, since it is larger than the sum of its proper divisors (9069650).

18139294 is an equidigital number, since it uses as much as digits as its factorization.

18139294 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9069649.

The product of its digits is 15552, while the sum is 37.

The square root of 18139294 is about 4259.0250057965. The cubic root of 18139294 is about 262.7484281561.

The spelling of 18139294 in words is "eighteen million, one hundred thirty-nine thousand, two hundred ninety-four".