816532649 has 2 divisors, whose sum is σ = 816532650. Its totient is φ = 816532648.

The previous prime is 816532643. The next prime is 816532663. The reversal of 816532649 is 946235618.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 757350400 + 59182249 = 27520^2 + 7693^2 .

It is a cyclic number.

It is not a de Polignac number, because 816532649 - 2²⁰ = 815484073 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 (816532643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 408266324 + 408266325.

It is an arithmetic number, because the mean of its divisors is an integer number (408266325).

Almost surely, 2^816532649 is an apocalyptic number.

It is an amenable number.

816532649 is a deficient number, since it is larger than the sum of its proper divisors (1).

816532649 is an equidigital number, since it uses as much as digits as its factorization.

816532649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 311040, while the sum is 44.

The square root of 816532649 is about 28575.0354155511. The cubic root of 816532649 is about 934.6690275268.

The spelling of 816532649 in words is "eight hundred sixteen million, five hundred thirty-two thousand, six hundred forty-nine".