891328609 has 2 divisors, whose sum is σ = 891328610. Its totient is φ = 891328608.

The previous prime is 891328597. The next prime is 891328657. The reversal of 891328609 is 906823198.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 643738384 + 247590225 = 25372^2 + 15735^2 .

It is a cyclic number.

It is not a de Polignac number, because 891328609 - 2⁵ = 891328577 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (891328679) 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, 445664304 + 445664305.

It is an arithmetic number, because the mean of its divisors is an integer number (445664305).

Almost surely, 2^891328609 is an apocalyptic number.

It is an amenable number.

891328609 is a deficient number, since it is larger than the sum of its proper divisors (1).

891328609 is an equidigital number, since it uses as much as digits as its factorization.

891328609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 186624, while the sum is 46.

The square root of 891328609 is about 29855.1270136303. The cubic root of 891328609 is about 962.3785812768.

The spelling of 891328609 in words is "eight hundred ninety-one million, three hundred twenty-eight thousand, six hundred nine".