20565006 has 48 divisors (see below), whose sum is σ = 52202880. Its totient is φ = 5340720.

The previous prime is 20565001. The next prime is 20565073. The reversal of 20565006 is 60056502.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20565001) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55 + ... + 6413.

It is an arithmetic number, because the mean of its divisors is an integer number (1087560).

Almost surely, 2^20565006 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20565006, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26101440).

20565006 is an abundant number, since it is smaller than the sum of its proper divisors (31637874).

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

20565006 is a wasteful number, since it uses less digits than its factorization.

20565006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6389 (or 6382 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 20565006 is about 4534.8655988904. The cubic root of 20565006 is about 273.9741659626.

The spelling of 20565006 in words is "twenty million, five hundred sixty-five thousand, six".