21664602960 has 640 divisors, whose sum is σ = 93114040320. Its totient is φ = 4020019200.

The previous prime is 21664602943. The next prime is 21664603013. The reversal of 21664602960 is 6920646612.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 7445986 + ... + 7448894.

It is an arithmetic number, because the mean of its divisors is an integer number (145490688).

Almost surely, 2^21664602960 is an apocalyptic number.

21664602960 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 21664602960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46557020160).

21664602960 is an abundant number, since it is smaller than the sum of its proper divisors (71449437360).

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

21664602960 is a wasteful number, since it uses less digits than its factorization.

21664602960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2987 (or 2981 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 42.

The spelling of 21664602960 in words is "twenty-one billion, six hundred sixty-four million, six hundred two thousand, nine hundred sixty".