805318649 has 2 divisors, whose sum is σ = 805318650. Its totient is φ = 805318648.

The previous prime is 805318643. The next prime is 805318681. The reversal of 805318649 is 946813508.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 620358649 + 184960000 = 24907^2 + 13600^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-805318649 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (805318643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 402659324 + 402659325.

It is an arithmetic number, because the mean of its divisors is an integer number (402659325).

Almost surely, 2^805318649 is an apocalyptic number.

It is an amenable number.

805318649 is a deficient number, since it is larger than the sum of its proper divisors (1).

805318649 is an equidigital number, since it uses as much as digits as its factorization.

805318649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 207360, while the sum is 44.

The square root of 805318649 is about 28378.1368133991. The cubic root of 805318649 is about 930.3704728952.

The spelling of 805318649 in words is "eight hundred five million, three hundred eighteen thousand, six hundred forty-nine".