209965213 has 2 divisors, whose sum is σ = 209965214. Its totient is φ = 209965212.

The previous prime is 209965193. The next prime is 209965237. The reversal of 209965213 is 312569902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 145033849 + 64931364 = 12043^2 + 8058^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-209965213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (209965243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104982606 + 104982607.

It is an arithmetic number, because the mean of its divisors is an integer number (104982607).

Almost surely, 2^209965213 is an apocalyptic number.

It is an amenable number.

209965213 is a deficient number, since it is larger than the sum of its proper divisors (1).

209965213 is an equidigital number, since it uses as much as digits as its factorization.

209965213 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 29160, while the sum is 37.

The square root of 209965213 is about 14490.1764309480. The cubic root of 209965213 is about 594.3593726364.

The spelling of 209965213 in words is "two hundred nine million, nine hundred sixty-five thousand, two hundred thirteen".