20644505541 has 12 divisors (see below), whose sum is σ = 32530736160. Its totient is φ = 12511821480.

The previous prime is 20644505527. The next prime is 20644505549. The reversal of 20644505541 is 14550544602.

20644505541 is a `hidden beast` number, since 2 + 0 + 64 + 4 + 50 + 5 + 541 = 666.

It is not a de Polignac number, because 20644505541 - 2⁹ = 20644505029 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20644505496 and 20644505505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20644505549) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 104265081 + ... + 104265278.

It is an arithmetic number, because the mean of its divisors is an integer number (2710894680).

Almost surely, 2^20644505541 is an apocalyptic number.

It is an amenable number.

20644505541 is a deficient number, since it is larger than the sum of its proper divisors (11886230619).

20644505541 is a wasteful number, since it uses less digits than its factorization.

20644505541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208530376 (or 208530373 counting only the distinct ones).

The product of its (nonzero) digits is 96000, while the sum is 36.

The spelling of 20644505541 in words is "twenty billion, six hundred forty-four million, five hundred five thousand, five hundred forty-one".