21611716655643 has 32 divisors (see below), whose sum is σ = 32456865039680. Its totient is φ = 14210044047360.

The previous prime is 21611716655591. The next prime is 21611716655647. The reversal of 21611716655643 is 34655661711612.

21611716655643 is a `hidden beast` number, since 2 + 1 + 6 + 1 + 1 + 7 + 16 + 65 + 564 + 3 = 666.

It is not a de Polignac number, because 21611716655643 - 2⁶ = 21611716655579 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21611716655643.

It is not an unprimeable number, because it can be changed into a prime (21611716655647) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 80663463 + ... + 80930943.

It is an arithmetic number, because the mean of its divisors is an integer number (1014277032490).

Almost surely, 2^{21611716655643} is an apocalyptic number.

21611716655643 is a deficient number, since it is larger than the sum of its proper divisors (10845148384037).

21611716655643 is a wasteful number, since it uses less digits than its factorization.

21611716655643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 308556 (or 308550 counting only the distinct ones).

The product of its digits is 5443200, while the sum is 54.

The spelling of 21611716655643 in words is "twenty-one trillion, six hundred eleven billion, seven hundred sixteen million, six hundred fifty-five thousand, six hundred forty-three".