221966117 has 2 divisors, whose sum is σ = 221966118. Its totient is φ = 221966116.

The previous prime is 221966111. The next prime is 221966119. The reversal of 221966117 is 711669122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 220641316 + 1324801 = 14854^2 + 1151^2 .

It is a cyclic number.

It is not a de Polignac number, because 221966117 - 2¹⁸ = 221703973 is a prime.

Together with 221966119, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221966111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110983058 + 110983059.

It is an arithmetic number, because the mean of its divisors is an integer number (110983059).

Almost surely, 2^221966117 is an apocalyptic number.

It is an amenable number.

221966117 is a deficient number, since it is larger than the sum of its proper divisors (1).

221966117 is an equidigital number, since it uses as much as digits as its factorization.

221966117 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 35.

The square root of 221966117 is about 14898.5273433316. The cubic root of 221966117 is about 605.4740877949.

The spelling of 221966117 in words is "two hundred twenty-one million, nine hundred sixty-six thousand, one hundred seventeen".