21660562522331 has 16 divisors (see below), whose sum is σ = 22372956822528. Its totient is φ = 20949026349600.

The previous prime is 21660562522309. The next prime is 21660562522429. The reversal of 21660562522331 is 13322526506612.

It is a cyclic number.

It is not a de Polignac number, because 21660562522331 - 2¹⁰ = 21660562521307 is a prime.

It is a super-2 number, since 2×21660562522331² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21660562524331) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 365876825 + ... + 365936021.

It is an arithmetic number, because the mean of its divisors is an integer number (1398309801408).

Almost surely, 2^{21660562522331} is an apocalyptic number.

21660562522331 is a deficient number, since it is larger than the sum of its proper divisors (712394300197).

21660562522331 is a wasteful number, since it uses less digits than its factorization.

21660562522331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66242.

The product of its (nonzero) digits is 777600, while the sum is 44.

The spelling of 21660562522331 in words is "twenty-one trillion, six hundred sixty billion, five hundred sixty-two million, five hundred twenty-two thousand, three hundred thirty-one".