819659849 has 2 divisors, whose sum is σ = 819659850. Its totient is φ = 819659848.

The previous prime is 819659831. The next prime is 819659887. The reversal of 819659849 is 948956918.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 446899600 + 372760249 = 21140^2 + 19307^2 .

It is a cyclic number.

It is not a de Polignac number, because 819659849 - 2²⁸ = 551224393 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (819659149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 409829924 + 409829925.

It is an arithmetic number, because the mean of its divisors is an integer number (409829925).

Almost surely, 2^819659849 is an apocalyptic number.

It is an amenable number.

819659849 is a deficient number, since it is larger than the sum of its proper divisors (1).

819659849 is an equidigital number, since it uses as much as digits as its factorization.

819659849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5598720, while the sum is 59.

The square root of 819659849 is about 28629.7022164046. The cubic root of 819659849 is about 935.8607224674.

The spelling of 819659849 in words is "eight hundred nineteen million, six hundred fifty-nine thousand, eight hundred forty-nine".