5556243221 has 2 divisors, whose sum is σ = 5556243222. Its totient is φ = 5556243220.

The previous prime is 5556243163. The next prime is 5556243223. The reversal of 5556243221 is 1223426555.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5319514225 + 236728996 = 72935^2 + 15386^2 .

It is a cyclic number.

It is not a de Polignac number, because 5556243221 - 2²² = 5552048917 is a prime.

Together with 5556243223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5556243223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2778121610 + 2778121611.

It is an arithmetic number, because the mean of its divisors is an integer number (2778121611).

Almost surely, 2^5556243221 is an apocalyptic number.

It is an amenable number.

5556243221 is a deficient number, since it is larger than the sum of its proper divisors (1).

5556243221 is an equidigital number, since it uses as much as digits as its factorization.

5556243221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72000, while the sum is 35.

The square root of 5556243221 is about 74540.2121072915. The cubic root of 5556243221 is about 1771.1706876472.

Adding to 5556243221 its reverse (1223426555), we get a palindrome (6779669776).

The spelling of 5556243221 in words is "five billion, five hundred fifty-six million, two hundred forty-three thousand, two hundred twenty-one".