21606612202660 has 24 divisors (see below), whose sum is σ = 45374383680696. Its totient is φ = 8642550013440.

The previous prime is 21606612202589. The next prime is 21606612202663. The reversal of 21606612202660 is 6620221660612.

It can be written as a sum of positive squares in 4 ways, for example, as 9918569189376 + 11688043013284 = 3149376^2 + 3418778^2 .

It is a super-2 number, since 2×21606612202660² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21606612202663) 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, 4047061 + ... + 7719580.

It is an arithmetic number, because the mean of its divisors is an integer number (1890599320029).

Almost surely, 2^{21606612202660} is an apocalyptic number.

21606612202660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21606612202660 is an abundant number, since it is smaller than the sum of its proper divisors (23767771478036).

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

21606612202660 is a wasteful number, since it uses less digits than its factorization.

21606612202660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11858463 (or 11858461 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 40.

The spelling of 21606612202660 in words is "twenty-one trillion, six hundred six billion, six hundred twelve million, two hundred two thousand, six hundred sixty".