5666636221 has 4 divisors (see below), whose sum is σ = 5862037500. Its totient is φ = 5471234944.

The previous prime is 5666636207. The next prime is 5666636233. The reversal of 5666636221 is 1226366665.

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 3234765625 + 2431870596 = 56875^2 + 49314^2 .

It is a cyclic number.

It is not a de Polignac number, because 5666636221 - 2¹⁷ = 5666505149 is a prime.

It is a super-2 number, since 2×5666636221² = 64221532122298321682, which 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 (5666636251) 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, 97700596 + ... + 97700653.

It is an arithmetic number, because the mean of its divisors is an integer number (1465509375).

Almost surely, 2^5666636221 is an apocalyptic number.

It is an amenable number.

5666636221 is a deficient number, since it is larger than the sum of its proper divisors (195401279).

5666636221 is a wasteful number, since it uses less digits than its factorization.

5666636221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195401278.

The product of its digits is 466560, while the sum is 43.

The square root of 5666636221 is about 75277.0630471195. The cubic root of 5666636221 is about 1782.8238875039.

The spelling of 5666636221 in words is "five billion, six hundred sixty-six million, six hundred thirty-six thousand, two hundred twenty-one".