18439356 has 72 divisors (see below), whose sum is σ = 49341040. Its totient is φ = 5326848.

The previous prime is 18439349. The next prime is 18439361. The reversal of 18439356 is 65393481.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 44880 + ... + 45288.

Almost surely, 2^18439356 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18439356, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24670520).

18439356 is an abundant number, since it is smaller than the sum of its proper divisors (30901684).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18439356 is a wasteful number, since it uses less digits than its factorization.

18439356 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 463 (or 444 counting only the distinct ones).

The product of its digits is 77760, while the sum is 39.

The square root of 18439356 is about 4294.1071248864. The cubic root of 18439356 is about 264.1893155401.

The spelling of 18439356 in words is "eighteen million, four hundred thirty-nine thousand, three hundred fifty-six".