21244423265 has 64 divisors (see below), whose sum is σ = 29115313920. Its totient is φ = 14774538240.

The previous prime is 21244423261. The next prime is 21244423267. The reversal of 21244423265 is 56232444212.

It is not a de Polignac number, because 21244423265 - 2² = 21244423261 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21244423261) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 10197914 + ... + 10199996.

It is an arithmetic number, because the mean of its divisors is an integer number (454926780).

Almost surely, 2^21244423265 is an apocalyptic number.

It is an amenable number.

21244423265 is a deficient number, since it is larger than the sum of its proper divisors (7870890655).

21244423265 is a wasteful number, since it uses less digits than its factorization.

21244423265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2274.

The product of its digits is 92160, while the sum is 35.

Adding to 21244423265 its reverse (56232444212), we get a palindrome (77476867477).

The spelling of 21244423265 in words is "twenty-one billion, two hundred forty-four million, four hundred twenty-three thousand, two hundred sixty-five".