320216891 has 2 divisors, whose sum is σ = 320216892. Its totient is φ = 320216890.

The previous prime is 320216873. The next prime is 320216893. The reversal of 320216891 is 198612023.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-320216891 is a prime.

Together with 320216893, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (320216893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160108445 + 160108446.

It is an arithmetic number, because the mean of its divisors is an integer number (160108446).

Almost surely, 2^320216891 is an apocalyptic number.

320216891 is a deficient number, since it is larger than the sum of its proper divisors (1).

320216891 is an equidigital number, since it uses as much as digits as its factorization.

320216891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 320216891 is about 17894.6050808617. The cubic root of 320216891 is about 684.1448764343.

The spelling of 320216891 in words is "three hundred twenty million, two hundred sixteen thousand, eight hundred ninety-one".