209072569 has 2 divisors, whose sum is σ = 209072570. Its totient is φ = 209072568.

The previous prime is 209072551. The next prime is 209072581. The reversal of 209072569 is 965270902.

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., 174556944 + 34515625 = 13212^2 + 5875^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-209072569 is a prime.

It is a super-2 number, since 2×209072569² = 87422678216519522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (209072519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104536284 + 104536285.

It is an arithmetic number, because the mean of its divisors is an integer number (104536285).

Almost surely, 2^209072569 is an apocalyptic number.

It is an amenable number.

209072569 is a deficient number, since it is larger than the sum of its proper divisors (1).

209072569 is an equidigital number, since it uses as much as digits as its factorization.

209072569 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 68040, while the sum is 40.

The square root of 209072569 is about 14459.3419283175. The cubic root of 209072569 is about 593.5158916913.

The spelling of 209072569 in words is "two hundred nine million, seventy-two thousand, five hundred sixty-nine".