21645614133 has 108 divisors (see below), whose sum is σ = 37430948100. Its totient is φ = 12038906880.

The previous prime is 21645614119. The next prime is 21645614141. The reversal of 21645614133 is 33141654612.

21645614133 is a `hidden beast` number, since 2 + 1 + 6 + 4 + 5 + 614 + 1 + 33 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 3106613169 + 18539000964 = 55737^2 + 136158^2 .

It is not a de Polignac number, because 21645614133 - 2¹⁶ = 21645548597 is a prime.

It is a super-2 number, since 2×21645614133² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21645614153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 62021643 + ... + 62021991.

Almost surely, 2^21645614133 is an apocalyptic number.

It is an amenable number.

21645614133 is a deficient number, since it is larger than the sum of its proper divisors (15785333967).

21645614133 is a wasteful number, since it uses less digits than its factorization.

21645614133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 740 (or 713 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The spelling of 21645614133 in words is "twenty-one billion, six hundred forty-five million, six hundred fourteen thousand, one hundred thirty-three".