10566515221 has 4 divisors (see below), whose sum is σ = 10739736844. Its totient is φ = 10393293600.

The previous prime is 10566515213. The next prime is 10566515237. The reversal of 10566515221 is 12251566501.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2215114225 + 8351400996 = 47065^2 + 91386^2 .

It is a cyclic number.

It is not a de Polignac number, because 10566515221 - 2³ = 10566515213 is a prime.

It is a super-2 number, since 2×10566515221² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10566515251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86610720 + ... + 86610841.

It is an arithmetic number, because the mean of its divisors is an integer number (2684934211).

Almost surely, 2^10566515221 is an apocalyptic number.

It is an amenable number.

10566515221 is a deficient number, since it is larger than the sum of its proper divisors (173221623).

10566515221 is an equidigital number, since it uses as much as digits as its factorization.

10566515221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173221622.

The product of its (nonzero) digits is 18000, while the sum is 34.

The spelling of 10566515221 in words is "ten billion, five hundred sixty-six million, five hundred fifteen thousand, two hundred twenty-one".