21765530705 has 8 divisors (see below), whose sum is σ = 26148423912. Its totient is φ = 17392566528.

The previous prime is 21765530701. The next prime is 21765530749. The reversal of 21765530705 is 50703556712.

It can be written as a sum of positive squares in 4 ways, for example, as 11996382784 + 9769147921 = 109528^2 + 98839^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21765530705 - 2² = 21765530701 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21765530701) 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, 2477432 + ... + 2486201.

It is an arithmetic number, because the mean of its divisors is an integer number (3268552989).

Almost surely, 2^21765530705 is an apocalyptic number.

It is an amenable number.

21765530705 is a deficient number, since it is larger than the sum of its proper divisors (4382893207).

21765530705 is an equidigital number, since it uses as much as digits as its factorization.

21765530705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4964515.

The product of its (nonzero) digits is 220500, while the sum is 41.

The spelling of 21765530705 in words is "twenty-one billion, seven hundred sixty-five million, five hundred thirty thousand, seven hundred five".