21606620611 has 16 divisors (see below), whose sum is σ = 23349531744. Its totient is φ = 19917474304.

The previous prime is 21606620561. The next prime is 21606620683. The reversal of 21606620611 is 11602660612.

It is a cyclic number.

It is not a de Polignac number, because 21606620611 - 2⁹ = 21606620099 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21606620111) 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, 508461 + ... + 549313.

It is an arithmetic number, because the mean of its divisors is an integer number (1459345734).

Almost surely, 2^21606620611 is an apocalyptic number.

21606620611 is a deficient number, since it is larger than the sum of its proper divisors (1742911133).

21606620611 is a wasteful number, since it uses less digits than its factorization.

21606620611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41510.

The product of its (nonzero) digits is 5184, while the sum is 31.

The spelling of 21606620611 in words is "twenty-one billion, six hundred six million, six hundred twenty thousand, six hundred eleven".