20564963 has 4 divisors (see below), whose sum is σ = 20796120. Its totient is φ = 20333808.

The previous prime is 20564941. The next prime is 20564969. The reversal of 20564963 is 36946502.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20564963 - 2⁶ = 20564899 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20564969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115445 + ... + 115622.

It is an arithmetic number, because the mean of its divisors is an integer number (5199030).

Almost surely, 2^20564963 is an apocalyptic number.

20564963 is a deficient number, since it is larger than the sum of its proper divisors (231157).

20564963 is an equidigital number, since it uses as much as digits as its factorization.

20564963 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231156.

The product of its (nonzero) digits is 38880, while the sum is 35.

The square root of 20564963 is about 4534.8608578434. The cubic root of 20564963 is about 273.9739750088.

The spelling of 20564963 in words is "twenty million, five hundred sixty-four thousand, nine hundred sixty-three".