221411221 has 2 divisors, whose sum is σ = 221411222. Its totient is φ = 221411220.

The previous prime is 221411191. The next prime is 221411227. The reversal of 221411221 is 122114122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 189612900 + 31798321 = 13770^2 + 5639^2 .

It is a cyclic number.

It is not a de Polignac number, because 221411221 - 2⁵ = 221411189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221411195 and 221411204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221411227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110705610 + 110705611.

It is an arithmetic number, because the mean of its divisors is an integer number (110705611).

Almost surely, 2^221411221 is an apocalyptic number.

It is an amenable number.

221411221 is a deficient number, since it is larger than the sum of its proper divisors (1).

221411221 is an equidigital number, since it uses as much as digits as its factorization.

221411221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64, while the sum is 16.

The square root of 221411221 is about 14879.8931783800. The cubic root of 221411221 is about 604.9691225732.

Adding to 221411221 its reverse (122114122), we get a palindrome (343525343).

The spelling of 221411221 in words is "two hundred twenty-one million, four hundred eleven thousand, two hundred twenty-one".