21826563265 has 16 divisors (see below), whose sum is σ = 28409572800. Its totient is φ = 16002113472.

The previous prime is 21826563263. The next prime is 21826563289. The reversal of 21826563265 is 56236562812.

It is a cyclic number.

It is not a de Polignac number, because 21826563265 - 2¹ = 21826563263 is a prime.

It is a super-2 number, since 2×21826563265² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21826563263) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1198855 + ... + 1216924.

It is an arithmetic number, because the mean of its divisors is an integer number (1775598300).

Almost surely, 2^21826563265 is an apocalyptic number.

It is an amenable number.

21826563265 is a deficient number, since it is larger than the sum of its proper divisors (6583009535).

21826563265 is a wasteful number, since it uses less digits than its factorization.

21826563265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2415936.

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

The spelling of 21826563265 in words is "twenty-one billion, eight hundred twenty-six million, five hundred sixty-three thousand, two hundred sixty-five".