18981924 has 48 divisors (see below), whose sum is σ = 47980800. Its totient is φ = 5806080.

The previous prime is 18981901. The next prime is 18981929. The reversal of 18981924 is 42918981.

It is not an unprimeable number, because it can be changed into a prime (18981929) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42052 + ... + 42500.

It is an arithmetic number, because the mean of its divisors is an integer number (999600).

Almost surely, 2^18981924 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 18981924, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23990400).

18981924 is an abundant number, since it is smaller than the sum of its proper divisors (28998876).

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

18981924 is a wasteful number, since it uses less digits than its factorization.

18981924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 740 (or 738 counting only the distinct ones).

The product of its digits is 41472, while the sum is 42.

The square root of 18981924 is about 4356.8249907473. The cubic root of 18981924 is about 266.7555169206.

The spelling of 18981924 in words is "eighteen million, nine hundred eighty-one thousand, nine hundred twenty-four".