20971247504256 has 3840 divisors, whose sum is σ = 85459325529600. Its totient is φ = 5056584744960.

The previous prime is 20971247504167. The next prime is 20971247504279. The reversal of 20971247504256 is 65240574217902.

It is a happy number.

20971247504256 is a `hidden beast` number, since 2 + 0 + 9 + 7 + 124 + 7 + 504 + 2 + 5 + 6 = 666.

It is a super-2 number, since 2×20971247504256² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 479 ways as a sum of consecutive naturals, for example, 287277363036 + ... + 287277363108.

It is an arithmetic number, because the mean of its divisors is an integer number (22255032690).

Almost surely, 2^{20971247504256} 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 20971247504256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42729662764800).

20971247504256 is an abundant number, since it is smaller than the sum of its proper divisors (64488078025344).

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

20971247504256 is a wasteful number, since it uses less digits than its factorization.

20971247504256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227 (or 199 counting only the distinct ones).

The product of its (nonzero) digits is 8467200, while the sum is 54.

The spelling of 20971247504256 in words is "twenty trillion, nine hundred seventy-one billion, two hundred forty-seven million, five hundred four thousand, two hundred fifty-six".