21765965885736 has 32 divisors (see below), whose sum is σ = 56291291085600. Its totient is φ = 7005138445760.

The previous prime is 21765965885669. The next prime is 21765965885737. The reversal of 21765965885736 is 63758856956712.

It is not an unprimeable number, because it can be changed into a prime (21765965885737) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15636469050 + ... + 15636470441.

It is an arithmetic number, because the mean of its divisors is an integer number (1759102846425).

Almost surely, 2^{21765965885736} is an apocalyptic number.

It is an amenable number.

21765965885736 is an abundant number, since it is smaller than the sum of its proper divisors (34525325199864).

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

21765965885736 is a wasteful number, since it uses less digits than its factorization.

21765965885736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31272939529 (or 31272939525 counting only the distinct ones).

The product of its digits is 4572288000, while the sum is 78.

The spelling of 21765965885736 in words is "twenty-one trillion, seven hundred sixty-five billion, nine hundred sixty-five million, eight hundred eighty-five thousand, seven hundred thirty-six".