221351213 has 2 divisors, whose sum is σ = 221351214. Its totient is φ = 221351212.

The previous prime is 221351201. The next prime is 221351219. The reversal of 221351213 is 312153122.

221351213 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 216590089 + 4761124 = 14717^2 + 2182^2 .

It is a cyclic number.

It is not a de Polignac number, because 221351213 - 2¹² = 221347117 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221351219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110675606 + 110675607.

It is an arithmetic number, because the mean of its divisors is an integer number (110675607).

Almost surely, 2^221351213 is an apocalyptic number.

It is an amenable number.

221351213 is a deficient number, since it is larger than the sum of its proper divisors (1).

221351213 is an equidigital number, since it uses as much as digits as its factorization.

221351213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 360, while the sum is 20.

The square root of 221351213 is about 14877.8766294119. The cubic root of 221351213 is about 604.9144636944.

The spelling of 221351213 in words is "two hundred twenty-one million, three hundred fifty-one thousand, two hundred thirteen".