809616901 has 2 divisors, whose sum is σ = 809616902. Its totient is φ = 809616900.

The previous prime is 809616893. The next prime is 809616937. The reversal of 809616901 is 109616908.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 739894401 + 69722500 = 27201^2 + 8350^2 .

It is a cyclic number.

It is not a de Polignac number, because 809616901 - 2³ = 809616893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (809616601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 404808450 + 404808451.

It is an arithmetic number, because the mean of its divisors is an integer number (404808451).

Almost surely, 2^809616901 is an apocalyptic number.

It is an amenable number.

809616901 is a deficient number, since it is larger than the sum of its proper divisors (1).

809616901 is an equidigital number, since it uses as much as digits as its factorization.

809616901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 40.

The square root of 809616901 is about 28453.7677821409. The cubic root of 809616901 is about 932.0227684056.

The spelling of 809616901 in words is "eight hundred nine million, six hundred sixteen thousand, nine hundred one".