21721112084560 has 40 divisors (see below), whose sum is σ = 57716097826176. Its totient is φ = 7447238428800.

The previous prime is 21721112084527. The next prime is 21721112084563. The reversal of 21721112084560 is 6548021112712.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21721112084563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19393849516 + ... + 19393850635.

Almost surely, 2^{21721112084560} is an apocalyptic number.

21721112084560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21721112084560 is an abundant number, since it is smaller than the sum of its proper divisors (35994985741616).

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

21721112084560 is a wasteful number, since it uses less digits than its factorization.

21721112084560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38787700171 (or 38787700165 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 40.

The spelling of 21721112084560 in words is "twenty-one trillion, seven hundred twenty-one billion, one hundred twelve million, eighty-four thousand, five hundred sixty".