99705209 has 2 divisors, whose sum is σ = 99705210. Its totient is φ = 99705208.

The previous prime is 99705191. The next prime is 99705223. The reversal of 99705209 is 90250799.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 92929600 + 6775609 = 9640^2 + 2603^2 .

It is a cyclic number.

It is not a de Polignac number, because 99705209 - 2⁸ = 99704953 is a prime.

It is a super-2 number, since 2×99705209² = 19882257403467362, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (99705239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49852604 + 49852605.

It is an arithmetic number, because the mean of its divisors is an integer number (49852605).

Almost surely, 2^99705209 is an apocalyptic number.

It is an amenable number.

99705209 is a deficient number, since it is larger than the sum of its proper divisors (1).

99705209 is an equidigital number, since it uses as much as digits as its factorization.

99705209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51030, while the sum is 41.

The square root of 99705209 is about 9985.2495712426. The cubic root of 99705209 is about 463.7023349078.

The spelling of 99705209 in words is "ninety-nine million, seven hundred five thousand, two hundred nine".