320777921 has 2 divisors, whose sum is σ = 320777922. Its totient is φ = 320777920.

The previous prime is 320777917. The next prime is 320777939. The reversal of 320777921 is 129777023.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 232135696 + 88642225 = 15236^2 + 9415^2 .

It is a cyclic number.

It is not a de Polignac number, because 320777921 - 2² = 320777917 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (320777621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160388960 + 160388961.

It is an arithmetic number, because the mean of its divisors is an integer number (160388961).

Almost surely, 2^320777921 is an apocalyptic number.

It is an amenable number.

320777921 is a deficient number, since it is larger than the sum of its proper divisors (1).

320777921 is an equidigital number, since it uses as much as digits as its factorization.

320777921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 37044, while the sum is 38.

The square root of 320777921 is about 17910.2741743392. The cubic root of 320777921 is about 684.5441910556.

The spelling of 320777921 in words is "three hundred twenty million, seven hundred seventy-seven thousand, nine hundred twenty-one".