20989504 has 56 divisors (see below), whose sum is σ = 44256960. Its totient is φ = 9859584.

The previous prime is 20989483. The next prime is 20989513. The reversal of 20989504 is 40598902.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79677 + ... + 79939.

Almost surely, 2^20989504 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 20989504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22128480).

20989504 is an abundant number, since it is smaller than the sum of its proper divisors (23267456).

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

20989504 is a wasteful number, since it uses less digits than its factorization.

20989504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347 (or 337 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 20989504 is about 4581.4303443357. The cubic root of 20989504 is about 275.8464454255.

The spelling of 20989504 in words is "twenty million, nine hundred eighty-nine thousand, five hundred four".