21265446063 has 4 divisors (see below), whose sum is σ = 28353928088. Its totient is φ = 14176964040.

The previous prime is 21265446049. The next prime is 21265446067. The reversal of 21265446063 is 36064456212.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21265446063 - 2²⁵ = 21231891631 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 (21265446067) 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, 3544241008 + ... + 3544241013.

It is an arithmetic number, because the mean of its divisors is an integer number (7088482022).

Almost surely, 2^21265446063 is an apocalyptic number.

21265446063 is a deficient number, since it is larger than the sum of its proper divisors (7088482025).

21265446063 is an equidigital number, since it uses as much as digits as its factorization.

21265446063 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7088482024.

The product of its (nonzero) digits is 207360, while the sum is 39.

The spelling of 21265446063 in words is "twenty-one billion, two hundred sixty-five million, four hundred forty-six thousand, sixty-three".