21620822608 has 160 divisors (see below), whose sum is σ = 55353600000. Its totient is φ = 7925506560.

The previous prime is 21620822593. The next prime is 21620822611. The reversal of 21620822608 is 80622802612.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3484693 + ... + 3490891.

It is an arithmetic number, because the mean of its divisors is an integer number (345960000).

Almost surely, 2^21620822608 is an apocalyptic number.

21620822608 is a gapful number since it is divisible by the number (28) 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 21620822608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27676800000).

21620822608 is an abundant number, since it is smaller than the sum of its proper divisors (33732777392).

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

21620822608 is a wasteful number, since it uses less digits than its factorization.

21620822608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6393 (or 6387 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 37.

The spelling of 21620822608 in words is "twenty-one billion, six hundred twenty million, eight hundred twenty-two thousand, six hundred eight".