9721322311680 has 1248 divisors, whose sum is σ = 40667442167040. Its totient is φ = 2098310676480.

The previous prime is 9721322311669. The next prime is 9721322311747. The reversal of 9721322311680 is 861132231279.

It is a happy number.

9721322311680 is a `hidden beast` number, since 9 + 7 + 2 + 1 + 322 + 311 + 6 + 8 + 0 = 666.

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

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, 13262376594 + ... + 13262377326.

It is an arithmetic number, because the mean of its divisors is an integer number (32586091480).

Almost surely, 2^{9721322311680} is an apocalyptic number.

9721322311680 is a gapful number since it is divisible by the number (90) 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 9721322311680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20333721083520).

9721322311680 is an abundant number, since it is smaller than the sum of its proper divisors (30946119855360).

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

9721322311680 is a wasteful number, since it uses less digits than its factorization.

9721322311680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1335 (or 1310 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The spelling of 9721322311680 in words is "nine trillion, seven hundred twenty-one billion, three hundred twenty-two million, three hundred eleven thousand, six hundred eighty".