21626117568 has 336 divisors, whose sum is σ = 71867633760. Its totient is φ = 6154444800.

The previous prime is 21626117561. The next prime is 21626117627. The reversal of 21626117568 is 86571162612.

21626117568 is a `hidden beast` number, since 2 + 1 + 626 + 1 + 17 + 5 + 6 + 8 = 666.

It is a super-2 number, since 2×21626117568² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21626117561) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6796938 + ... + 6800118.

Almost surely, 2^21626117568 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 21626117568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35933816880).

21626117568 is an abundant number, since it is smaller than the sum of its proper divisors (50241516192).

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

21626117568 is a wasteful number, since it uses less digits than its factorization.

21626117568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3276 (or 3263 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The spelling of 21626117568 in words is "twenty-one billion, six hundred twenty-six million, one hundred seventeen thousand, five hundred sixty-eight".