18439680 has 200 divisors, whose sum is σ = 68770152. Its totient is φ = 4214784.

The previous prime is 18439669. The next prime is 18439693. The reversal of 18439680 is 8693481.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2634237 + ... + 2634243.

Almost surely, 2^18439680 is an apocalyptic number.

18439680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18439680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34385076).

18439680 is an abundant number, since it is smaller than the sum of its proper divisors (50330472).

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

18439680 is an frugal number, since it uses more digits than its factorization.

18439680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54 (or 17 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 39.

The square root of 18439680 is about 4294.1448508405. The cubic root of 18439680 is about 264.1908628977.

The spelling of 18439680 in words is "eighteen million, four hundred thirty-nine thousand, six hundred eighty".