20564212661065 has 32 divisors (see below), whose sum is σ = 26552708485632. Its totient is φ = 15250614720000.

The previous prime is 20564212661029. The next prime is 20564212661087. The reversal of 20564212661065 is 56016621246502.

It is not a de Polignac number, because 20564212661065 - 2⁹ = 20564212660553 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13729906 + ... + 15153835.

It is an arithmetic number, because the mean of its divisors is an integer number (829772140176).

Almost surely, 2^{20564212661065} is an apocalyptic number.

It is an amenable number.

20564212661065 is a deficient number, since it is larger than the sum of its proper divisors (5988495824567).

20564212661065 is a wasteful number, since it uses less digits than its factorization.

20564212661065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28883961.

The product of its (nonzero) digits is 1036800, while the sum is 46.

The spelling of 20564212661065 in words is "twenty trillion, five hundred sixty-four billion, two hundred twelve million, six hundred sixty-one thousand, sixty-five".