21023108065 has 8 divisors (see below), whose sum is σ = 25397044200. Its totient is φ = 16705610112.

The previous prime is 21023108063. The next prime is 21023108077. The reversal of 21023108065 is 56080132012.

It can be written as a sum of positive squares in 4 ways, for example, as 3679271649 + 17343836416 = 60657^2 + 131696^2 .

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 21023108065 - 2¹ = 21023108063 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21023108063) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14108724 + ... + 14110213.

It is an arithmetic number, because the mean of its divisors is an integer number (3174630525).

Almost surely, 2^21023108065 is an apocalyptic number.

It is an amenable number.

21023108065 is a deficient number, since it is larger than the sum of its proper divisors (4373936135).

21023108065 is a wasteful number, since it uses less digits than its factorization.

21023108065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28219091.

The product of its (nonzero) digits is 2880, while the sum is 28.

The spelling of 21023108065 in words is "twenty-one billion, twenty-three million, one hundred eight thousand, sixty-five".