556224251221 has 2 divisors, whose sum is σ = 556224251222. Its totient is φ = 556224251220.

The previous prime is 556224251203. The next prime is 556224251237. The reversal of 556224251221 is 122152422655.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 552069804196 + 4154447025 = 743014^2 + 64455^2 .

It is a cyclic number.

It is not a de Polignac number, because 556224251221 - 2²³ = 556215862613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (556224251201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 278112125610 + 278112125611.

It is an arithmetic number, because the mean of its divisors is an integer number (278112125611).

Almost surely, 2^556224251221 is an apocalyptic number.

It is an amenable number.

556224251221 is a deficient number, since it is larger than the sum of its proper divisors (1).

556224251221 is an equidigital number, since it uses as much as digits as its factorization.

556224251221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96000, while the sum is 37.

Adding to 556224251221 its reverse (122152422655), we get a palindrome (678376673876).

The spelling of 556224251221 in words is "five hundred fifty-six billion, two hundred twenty-four million, two hundred fifty-one thousand, two hundred twenty-one".