21929656320 has 684 divisors, whose sum is σ = 89804071656. Its totient is φ = 4907335680.

The previous prime is 21929656319. The next prime is 21929656381. The reversal of 21929656320 is 2365692912.

21929656320 is a `hidden beast` number, since 2 + 1 + 9 + 2 + 9 + 6 + 5 + 632 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1686896634 + ... + 1686896646.

Almost surely, 2^21929656320 is an apocalyptic number.

21929656320 is a gapful number since it is divisible by the number (20) 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 21929656320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44902035828).

21929656320 is an abundant number, since it is smaller than the sum of its proper divisors (67874415336).

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

21929656320 is an equidigital number, since it uses as much as digits as its factorization.

21929656320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84 (or 34 counting only the distinct ones).

The product of its (nonzero) digits is 349920, while the sum is 45.

The spelling of 21929656320 in words is "twenty-one billion, nine hundred twenty-nine million, six hundred fifty-six thousand, three hundred twenty".