20505411636 has 24 divisors (see below), whose sum is σ = 47859850080. Its totient is φ = 6833152992.

The previous prime is 20505411607. The next prime is 20505411659. The reversal of 20505411636 is 63611450502.

It is a junction number, because it is equal to n+sod(n) for n = 20505411597 and 20505411606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 204666 + ... + 287921.

It is an arithmetic number, because the mean of its divisors is an integer number (1994160420).

Almost surely, 2^20505411636 is an apocalyptic number.

It is an amenable number.

20505411636 is an abundant number, since it is smaller than the sum of its proper divisors (27354438444).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20505411636 is a wasteful number, since it uses less digits than its factorization.

20505411636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 496063 (or 496061 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 33.

The spelling of 20505411636 in words is "twenty billion, five hundred five million, four hundred eleven thousand, six hundred thirty-six".