18439949 has 8 divisors (see below), whose sum is σ = 20660448. Its totient is φ = 16310160.

The previous prime is 18439921. The next prime is 18439961. The reversal of 18439949 is 94993481.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18439949 - 2⁸ = 18439693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18439909) 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 7 ways as a sum of consecutive naturals, for example, 22247 + ... + 23060.

It is an arithmetic number, because the mean of its divisors is an integer number (2582556).

Almost surely, 2^18439949 is an apocalyptic number.

It is an amenable number.

18439949 is a deficient number, since it is larger than the sum of its proper divisors (2220499).

18439949 is a wasteful number, since it uses less digits than its factorization.

18439949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45355.

The product of its digits is 279936, while the sum is 47.

The square root of 18439949 is about 4294.1761724457. The cubic root of 18439949 is about 264.1921475729.

The spelling of 18439949 in words is "eighteen million, four hundred thirty-nine thousand, nine hundred forty-nine".