868660409 has 2 divisors, whose sum is σ = 868660410. Its totient is φ = 868660408.

The previous prime is 868660367. The next prime is 868660447. The reversal of 868660409 is 904066868.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 735765625 + 132894784 = 27125^2 + 11528^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-868660409 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (868660459) 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, 434330204 + 434330205.

It is an arithmetic number, because the mean of its divisors is an integer number (434330205).

Almost surely, 2^868660409 is an apocalyptic number.

It is an amenable number.

868660409 is a deficient number, since it is larger than the sum of its proper divisors (1).

868660409 is an equidigital number, since it uses as much as digits as its factorization.

868660409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 497664, while the sum is 47.

The square root of 868660409 is about 29473.0454653061. The cubic root of 868660409 is about 954.1500470128.

The spelling of 868660409 in words is "eight hundred sixty-eight million, six hundred sixty thousand, four hundred nine".