18919680 has 144 divisors (see below), whose sum is σ = 65244480. Its totient is φ = 4644864.

The previous prime is 18919673. The next prime is 18919697. The reversal of 18919680 is 8691981.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49731 + ... + 50109.

Almost surely, 2^18919680 is an apocalyptic number.

18919680 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 18919680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32622240).

18919680 is an abundant number, since it is smaller than the sum of its proper divisors (46324800).

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

18919680 is a wasteful number, since it uses less digits than its factorization.

18919680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416 (or 402 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 42.

The square root of 18919680 is about 4349.6758499916. The cubic root of 18919680 is about 266.4636232171.

The spelling of 18919680 in words is "eighteen million, nine hundred nineteen thousand, six hundred eighty".