319855220921 has 2 divisors, whose sum is σ = 319855220922. Its totient is φ = 319855220920.

The previous prime is 319855220899. The next prime is 319855220939. The reversal of 319855220921 is 129022558913.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 222878410000 + 96976810921 = 472100^2 + 311411^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-319855220921 is a prime.

It is not a weakly prime, because it can be changed into another prime (319855220941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159927610460 + 159927610461.

It is an arithmetic number, because the mean of its divisors is an integer number (159927610461).

Almost surely, 2^319855220921 is an apocalyptic number.

It is an amenable number.

319855220921 is a deficient number, since it is larger than the sum of its proper divisors (1).

319855220921 is an equidigital number, since it uses as much as digits as its factorization.

319855220921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 388800, while the sum is 47.

The spelling of 319855220921 in words is "three hundred nineteen billion, eight hundred fifty-five million, two hundred twenty thousand, nine hundred twenty-one".