209110997 has 2 divisors, whose sum is σ = 209110998. Its totient is φ = 209110996.

The previous prime is 209110981. The next prime is 209111011. The reversal of 209110997 is 799011902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 208542481 + 568516 = 14441^2 + 754^2 .

It is a cyclic number.

It is not a de Polignac number, because 209110997 - 2⁴ = 209110981 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 209110997.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (209110397) 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, 104555498 + 104555499.

It is an arithmetic number, because the mean of its divisors is an integer number (104555499).

Almost surely, 2^209110997 is an apocalyptic number.

It is an amenable number.

209110997 is a deficient number, since it is larger than the sum of its proper divisors (1).

209110997 is an equidigital number, since it uses as much as digits as its factorization.

209110997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10206, while the sum is 38.

The square root of 209110997 is about 14460.6706967554. The cubic root of 209110997 is about 593.5522526410.

The spelling of 209110997 in words is "two hundred nine million, one hundred ten thousand, nine hundred ninety-seven".