221301209 has 2 divisors, whose sum is σ = 221301210. Its totient is φ = 221301208.

The previous prime is 221301203. The next prime is 221301251. The reversal of 221301209 is 902103122.

221301209 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., 197486809 + 23814400 = 14053^2 + 4880^2 .

It is a cyclic number.

It is not a de Polignac number, because 221301209 - 2⁸ = 221300953 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (221301203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110650604 + 110650605.

It is an arithmetic number, because the mean of its divisors is an integer number (110650605).

Almost surely, 2^221301209 is an apocalyptic number.

It is an amenable number.

221301209 is a deficient number, since it is larger than the sum of its proper divisors (1).

221301209 is an equidigital number, since it uses as much as digits as its factorization.

221301209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 221301209 is about 14876.1960527549. The cubic root of 221301209 is about 604.8689095116.

The spelling of 221301209 in words is "two hundred twenty-one million, three hundred one thousand, two hundred nine".