21245326065 has 12 divisors (see below), whose sum is σ = 36825231924. Its totient is φ = 11330840544.

The previous prime is 21245326057. The next prime is 21245326103. The reversal of 21245326065 is 56062354212.

21245326065 is a `hidden beast` number, since 2 + 1 + 2 + 4 + 532 + 60 + 65 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 15930478656 + 5314847409 = 126216^2 + 72903^2 .

It is not a de Polignac number, because 21245326065 - 2³ = 21245326057 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 236059134 + ... + 236059223.

It is an arithmetic number, because the mean of its divisors is an integer number (3068769327).

Almost surely, 2^21245326065 is an apocalyptic number.

It is an amenable number.

21245326065 is a deficient number, since it is larger than the sum of its proper divisors (15579905859).

21245326065 is a wasteful number, since it uses less digits than its factorization.

21245326065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472118368 (or 472118365 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The spelling of 21245326065 in words is "twenty-one billion, two hundred forty-five million, three hundred twenty-six thousand, sixty-five".