21027617110656 has 1024 divisors, whose sum is σ = 74833926451200. Its totient is φ = 5749014528000.

The previous prime is 21027617110601. The next prime is 21027617110663. The reversal of 21027617110656 is 65601171672012.

21027617110656 is a `hidden beast` number, since 2 + 1 + 0 + 27 + 617 + 1 + 1 + 0 + 6 + 5 + 6 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 970748466 + ... + 970770126.

It is an arithmetic number, because the mean of its divisors is an integer number (73080006300).

Almost surely, 2^{21027617110656} is an apocalyptic number.

21027617110656 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21027617110656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37416963225600).

21027617110656 is an abundant number, since it is smaller than the sum of its proper divisors (53806309340544).

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

21027617110656 is a wasteful number, since it uses less digits than its factorization.

21027617110656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21786 (or 21768 counting only the distinct ones).

The product of its (nonzero) digits is 211680, while the sum is 45.

Adding to 21027617110656 its reverse (65601171672012), we get a palindrome (86628788782668).

The spelling of 21027617110656 in words is "twenty-one trillion, twenty-seven billion, six hundred seventeen million, one hundred ten thousand, six hundred fifty-six".