21991076698320 has 640 divisors, whose sum is σ = 82304907148800. Its totient is φ = 5376166428672.

The previous prime is 21991076698307. The next prime is 21991076698333. The reversal of 21991076698320 is 2389667019912.

21991076698320 is a `hidden beast` number, since 219 + 9 + 1 + 0 + 7 + 6 + 6 + 98 + 320 = 666.

It is an interprime number because it is at equal distance from previous prime (21991076698307) and next prime (21991076698333).

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 127 ways as a sum of consecutive naturals, for example, 270475594 + ... + 270556886.

It is an arithmetic number, because the mean of its divisors is an integer number (128601417420).

Almost surely, 2^{21991076698320} is an apocalyptic number.

21991076698320 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 21991076698320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41152453574400).

21991076698320 is an abundant number, since it is smaller than the sum of its proper divisors (60313830450480).

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

21991076698320 is a wasteful number, since it uses less digits than its factorization.

21991076698320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81524 (or 81512 counting only the distinct ones).

The product of its (nonzero) digits is 17635968, while the sum is 63.

The spelling of 21991076698320 in words is "twenty-one trillion, nine hundred ninety-one billion, seventy-six million, six hundred ninety-eight thousand, three hundred twenty".