207243221 has 2 divisors, whose sum is σ = 207243222. Its totient is φ = 207243220.

The previous prime is 207243181. The next prime is 207243227. The reversal of 207243221 is 122342702.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 206956996 + 286225 = 14386^2 + 535^2 .

It is a cyclic number.

It is not a de Polignac number, because 207243221 - 2¹⁰ = 207242197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (207243227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103621610 + 103621611.

It is an arithmetic number, because the mean of its divisors is an integer number (103621611).

Almost surely, 2^207243221 is an apocalyptic number.

It is an amenable number.

207243221 is a deficient number, since it is larger than the sum of its proper divisors (1).

207243221 is an equidigital number, since it uses as much as digits as its factorization.

207243221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 207243221 is about 14395.9446025608. The cubic root of 207243221 is about 591.7797651767.

Adding to 207243221 its reverse (122342702), we get a palindrome (329585923).

The spelling of 207243221 in words is "two hundred seven million, two hundred forty-three thousand, two hundred twenty-one".