97866809 has 2 divisors, whose sum is σ = 97866810. Its totient is φ = 97866808.

The previous prime is 97866799. The next prime is 97866869. The reversal of 97866809 is 90866879.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 81504784 + 16362025 = 9028^2 + 4045^2 .

It is an emirp because it is prime and its reverse (90866879) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 97866809 - 2⁸ = 97866553 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (97866869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 48933404 + 48933405.

It is an arithmetic number, because the mean of its divisors is an integer number (48933405).

Almost surely, 2^97866809 is an apocalyptic number.

It is an amenable number.

97866809 is a deficient number, since it is larger than the sum of its proper divisors (1).

97866809 is an equidigital number, since it uses as much as digits as its factorization.

97866809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1306368, while the sum is 53.

The square root of 97866809 is about 9892.7654879715. The cubic root of 97866809 is about 460.8346676336.

The spelling of 97866809 in words is "ninety-seven million, eight hundred sixty-six thousand, eight hundred nine".