20564825 has 12 divisors (see below), whose sum is σ = 25584300. Its totient is φ = 16397760.

The previous prime is 20564807. The next prime is 20564833. The reversal of 20564825 is 52846502.

It can be written as a sum of positive squares in 6 ways, for example, as 753424 + 19811401 = 868^2 + 4451^2 .

It is a de Polignac number, because none of the positive numbers 2^k-20564825 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20564791 and 20564800.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7547 + ... + 9903.

It is an arithmetic number, because the mean of its divisors is an integer number (2132025).

Almost surely, 2^20564825 is an apocalyptic number.

20564825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20564825 is a deficient number, since it is larger than the sum of its proper divisors (5019475).

20564825 is a wasteful number, since it uses less digits than its factorization.

20564825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2716 (or 2711 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 32.

The square root of 20564825 is about 4534.8456423565. The cubic root of 20564825 is about 273.9733621785.

The spelling of 20564825 in words is "twenty million, five hundred sixty-four thousand, eight hundred twenty-five".