20560921 has 2 divisors, whose sum is σ = 20560922. Its totient is φ = 20560920.

The previous prime is 20560909. The next prime is 20560933. The reversal of 20560921 is 12906502.

It is a balanced prime because it is at equal distance from previous prime (20560909) and next prime (20560933).

It can be written as a sum of positive squares in only one way, i.e., 17338896 + 3222025 = 4164^2 + 1795^2 .

It is a cyclic number.

It is not a de Polignac number, because 20560921 - 2⁵ = 20560889 is a prime.

It is not a weakly prime, because it can be changed into another prime (20560901) by changing a digit.

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 as a sum of consecutive naturals, namely, 10280460 + 10280461.

It is an arithmetic number, because the mean of its divisors is an integer number (10280461).

Almost surely, 2^20560921 is an apocalyptic number.

It is an amenable number.

20560921 is a deficient number, since it is larger than the sum of its proper divisors (1).

20560921 is an equidigital number, since it uses as much as digits as its factorization.

20560921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 20560921 is about 4534.4151772858. The cubic root of 20560921 is about 273.9560241641.

The spelling of 20560921 in words is "twenty million, five hundred sixty thousand, nine hundred twenty-one".