20641584 has 40 divisors (see below), whose sum is σ = 53835840. Its totient is φ = 6814528.

The previous prime is 20641571. The next prime is 20641589. The reversal of 20641584 is 48514602.

It is not an unprimeable number, because it can be changed into a prime (20641589) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3127 + ... + 7145.

It is an arithmetic number, because the mean of its divisors is an integer number (1345896).

Almost surely, 2^20641584 is an apocalyptic number.

20641584 is a gapful number since it is divisible by the number (24) 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 20641584, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26917920).

20641584 is an abundant number, since it is smaller than the sum of its proper divisors (33194256).

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

20641584 is a wasteful number, since it uses less digits than its factorization.

20641584 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4137 (or 4131 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 30.

The square root of 20641584 is about 4543.3010025751. The cubic root of 20641584 is about 274.3138109859.

The spelling of 20641584 in words is "twenty million, six hundred forty-one thousand, five hundred eighty-four".