21465065653 has 4 divisors (see below), whose sum is σ = 21628921248. Its totient is φ = 21301210060.

The previous prime is 21465065647. The next prime is 21465065669. The reversal of 21465065653 is 35656056412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21465065653 - 2⁵ = 21465065621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21465065753) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 81927601 + ... + 81927862.

It is an arithmetic number, because the mean of its divisors is an integer number (5407230312).

Almost surely, 2^21465065653 is an apocalyptic number.

It is an amenable number.

21465065653 is a deficient number, since it is larger than the sum of its proper divisors (163855595).

21465065653 is a wasteful number, since it uses less digits than its factorization.

21465065653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163855594.

The product of its (nonzero) digits is 648000, while the sum is 43.

The spelling of 21465065653 in words is "twenty-one billion, four hundred sixty-five million, sixty-five thousand, six hundred fifty-three".