221563213 has 2 divisors, whose sum is σ = 221563214. Its totient is φ = 221563212.

The previous prime is 221563201. The next prime is 221563241. The reversal of 221563213 is 312365122.

221563213 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 132204004 + 89359209 = 11498^2 + 9453^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221563213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221563513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110781606 + 110781607.

It is an arithmetic number, because the mean of its divisors is an integer number (110781607).

Almost surely, 2^221563213 is an apocalyptic number.

It is an amenable number.

221563213 is a deficient number, since it is larger than the sum of its proper divisors (1).

221563213 is an equidigital number, since it uses as much as digits as its factorization.

221563213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160, while the sum is 25.

The square root of 221563213 is about 14884.9995969096. Note that the first 3 decimals coincide. The cubic root of 221563213 is about 605.1075218138.

The spelling of 221563213 in words is "two hundred twenty-one million, five hundred sixty-three thousand, two hundred thirteen".