646033691 has 2 divisors, whose sum is σ = 646033692. Its totient is φ = 646033690.

The previous prime is 646033669. The next prime is 646033697. The reversal of 646033691 is 196330646.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 646033691 - 2⁶ = 646033627 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (646033697) 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, 323016845 + 323016846.

It is an arithmetic number, because the mean of its divisors is an integer number (323016846).

Almost surely, 2^646033691 is an apocalyptic number.

646033691 is a deficient number, since it is larger than the sum of its proper divisors (1).

646033691 is an equidigital number, since it uses as much as digits as its factorization.

646033691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 69984, while the sum is 38.

The square root of 646033691 is about 25417.1928229693. The cubic root of 646033691 is about 864.4735750213.

The spelling of 646033691 in words is "six hundred forty-six million, thirty-three thousand, six hundred ninety-one".