319843721 has 2 divisors, whose sum is σ = 319843722. Its totient is φ = 319843720.

The previous prime is 319843687. The next prime is 319843723. The reversal of 319843721 is 127348913.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 262083721 + 57760000 = 16189^2 + 7600^2 .

It is a cyclic number.

It is not a de Polignac number, because 319843721 - 2²⁶ = 252734857 is a prime.

Together with 319843723, 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 (319843723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159921860 + 159921861.

It is an arithmetic number, because the mean of its divisors is an integer number (159921861).

Almost surely, 2^319843721 is an apocalyptic number.

It is an amenable number.

319843721 is a deficient number, since it is larger than the sum of its proper divisors (1).

319843721 is an equidigital number, since it uses as much as digits as its factorization.

319843721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 38.

The square root of 319843721 is about 17884.1751557068. The cubic root of 319843721 is about 683.8790133182.

The spelling of 319843721 in words is "three hundred nineteen million, eight hundred forty-three thousand, seven hundred twenty-one".