810616649 has 2 divisors, whose sum is σ = 810616650. Its totient is φ = 810616648.

The previous prime is 810616621. The next prime is 810616663. The reversal of 810616649 is 946616018.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 481012624 + 329604025 = 21932^2 + 18155^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-810616649 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (810616679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405308324 + 405308325.

It is an arithmetic number, because the mean of its divisors is an integer number (405308325).

Almost surely, 2^810616649 is an apocalyptic number.

It is an amenable number.

810616649 is a deficient number, since it is larger than the sum of its proper divisors (1).

810616649 is an equidigital number, since it uses as much as digits as its factorization.

810616649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 62208, while the sum is 41.

The square root of 810616649 is about 28471.3302990921. The cubic root of 810616649 is about 932.4062438591.

The spelling of 810616649 in words is "eight hundred ten million, six hundred sixteen thousand, six hundred forty-nine".