20564224966656 has 1836 divisors, whose sum is σ = 76672486478952. Its totient is φ = 5490006294528.

The previous prime is 20564224966643. The next prime is 20564224966673. The reversal of 20564224966656 is 65666942246502.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 20564224966593 and 20564224966602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 281701711836 + ... + 281701711908.

Almost surely, 2^{20564224966656} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20564224966656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38336243239476).

20564224966656 is an abundant number, since it is smaller than the sum of its proper divisors (56108261512296).

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

20564224966656 is an frugal number, since it uses more digits than its factorization.

20564224966656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172 (or 104 counting only the distinct ones).

The product of its (nonzero) digits is 223948800, while the sum is 63.

The spelling of 20564224966656 in words is "twenty trillion, five hundred sixty-four billion, two hundred twenty-four million, nine hundred sixty-six thousand, six hundred fifty-six".