20256570 has 48 divisors (see below), whose sum is σ = 53012232. Its totient is φ = 5366400.

The previous prime is 20256559. The next prime is 20256581. The reversal of 20256570 is 7565202.

20256570 is a `hidden beast` number, since 2 + 0 + 2 + 5 + 657 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (20256559) and next prime (20256581).

It can be written as a sum of positive squares in 4 ways, for example, as 13860729 + 6395841 = 3723^2 + 2529^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14920 + ... + 16220.

Almost surely, 2^20256570 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20256570, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26506116).

20256570 is an abundant number, since it is smaller than the sum of its proper divisors (32755662).

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

20256570 is a wasteful number, since it uses less digits than its factorization.

20256570 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1487 (or 1484 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 27.

The square root of 20256570 is about 4500.7299407985. The cubic root of 20256570 is about 272.5975634715.

The spelling of 20256570 in words is "twenty million, two hundred fifty-six thousand, five hundred seventy".