21628625365 has 16 divisors (see below), whose sum is σ = 26135961840. Its totient is φ = 17181964800.

The previous prime is 21628625353. The next prime is 21628625371. The reversal of 21628625365 is 56352682612.

It can be written as a sum of positive squares in 8 ways, for example, as 4075290244 + 17553335121 = 63838^2 + 132489^2 .

It is not a de Polignac number, because 21628625365 - 2²⁵ = 21595070933 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1396665 + ... + 1412065.

It is an arithmetic number, because the mean of its divisors is an integer number (1633497615).

Almost surely, 2^21628625365 is an apocalyptic number.

It is an amenable number.

21628625365 is a deficient number, since it is larger than the sum of its proper divisors (4507336475).

21628625365 is a wasteful number, since it uses less digits than its factorization.

21628625365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17352.

The product of its digits is 1036800, while the sum is 46.

The spelling of 21628625365 in words is "twenty-one billion, six hundred twenty-eight million, six hundred twenty-five thousand, three hundred sixty-five".