21663034041664 has 28 divisors (see below), whose sum is σ = 42991059053524. Its totient is φ = 10830641209344.

The previous prime is 21663034041643. The next prime is 21663034041667. The reversal of 21663034041664 is 46614043036612.

It can be written as a sum of positive squares in 2 ways, for example, as 14916588840000 + 6746445201664 = 3862200^2 + 2597392^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21663034041667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12886497 + ... + 14470240.

Almost surely, 2^{21663034041664} is an apocalyptic number.

It is an amenable number.

21663034041664 is a deficient number, since it is larger than the sum of its proper divisors (21328025011860).

21663034041664 is a wasteful number, since it uses less digits than its factorization.

21663034041664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27369122 (or 27369112 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 46.

The spelling of 21663034041664 in words is "twenty-one trillion, six hundred sixty-three billion, thirty-four million, forty-one thousand, six hundred sixty-four".