320211809 has 2 divisors, whose sum is σ = 320211810. Its totient is φ = 320211808.

The previous prime is 320211797. The next prime is 320211817. The reversal of 320211809 is 908112023.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 303630625 + 16581184 = 17425^2 + 4072^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-320211809 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (320211839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160105904 + 160105905.

It is an arithmetic number, because the mean of its divisors is an integer number (160105905).

Almost surely, 2^320211809 is an apocalyptic number.

It is an amenable number.

320211809 is a deficient number, since it is larger than the sum of its proper divisors (1).

320211809 is an equidigital number, since it uses as much as digits as its factorization.

320211809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 320211809 is about 17894.4630821939. The cubic root of 320211809 is about 684.1412571763.

The spelling of 320211809 in words is "three hundred twenty million, two hundred eleven thousand, eight hundred nine".