20565104 has 60 divisors (see below), whose sum is σ = 49108464. Its totient is φ = 8289792.

The previous prime is 20565101. The next prime is 20565107. The reversal of 20565104 is 40156502.

It is an interprime number because it is at equal distance from previous prime (20565101) and next prime (20565107).

It is a self number, because there is not a number n which added to its sum of digits gives 20565104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20565101) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12557 + ... + 14099.

Almost surely, 2^20565104 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 20565104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24554232).

20565104 is an abundant number, since it is smaller than the sum of its proper divisors (28543360).

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

20565104 is a wasteful number, since it uses less digits than its factorization.

20565104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1582 (or 1569 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 20565104 is about 4534.8764040490. The cubic root of 20565104 is about 273.9746011586.

The spelling of 20565104 in words is "twenty million, five hundred sixty-five thousand, one hundred four".