21726822656 has 216 divisors, whose sum is σ = 55616258880. Its totient is φ = 8375808000.

The previous prime is 21726822653. The next prime is 21726822673. The reversal of 21726822656 is 65622862712.

It is a happy number.

Its product of digits (967680) is a multiple of the sum of its prime divisors (1680).

It is a self number, because there is not a number n which added to its sum of digits gives 21726822656.

It is not an unprimeable number, because it can be changed into a prime (21726822653) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13935605 + ... + 13937163.

It is an arithmetic number, because the mean of its divisors is an integer number (257482680).

Almost surely, 2^21726822656 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 21726822656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27808129440).

21726822656 is an abundant number, since it is smaller than the sum of its proper divisors (33889436224).

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

21726822656 is a wasteful number, since it uses less digits than its factorization.

21726822656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1701 (or 1680 counting only the distinct ones).

The product of its digits is 967680, while the sum is 47.

The spelling of 21726822656 in words is "twenty-one billion, seven hundred twenty-six million, eight hundred twenty-two thousand, six hundred fifty-six".