21716816840320 has 768 divisors, whose sum is σ = 66641054054400. Its totient is φ = 6723905126400.

The previous prime is 21716816840311. The next prime is 21716816840339. The reversal of 21716816840320 is 2304861861712.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 916735036 + ... + 916758724.

It is an arithmetic number, because the mean of its divisors is an integer number (86772205800).

Almost surely, 2^{21716816840320} is an apocalyptic number.

21716816840320 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 21716816840320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33320527027200).

21716816840320 is an abundant number, since it is smaller than the sum of its proper divisors (44924237214080).

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

21716816840320 is a wasteful number, since it uses less digits than its factorization.

21716816840320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23817 (or 23798 counting only the distinct ones).

The product of its (nonzero) digits is 774144, while the sum is 49.

The spelling of 21716816840320 in words is "twenty-one trillion, seven hundred sixteen billion, eight hundred sixteen million, eight hundred forty thousand, three hundred twenty".