671319709 has 2 divisors, whose sum is σ = 671319710. Its totient is φ = 671319708.

The previous prime is 671319707. The next prime is 671319721. The reversal of 671319709 is 907913176.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 463325625 + 207994084 = 21525^2 + 14422^2 .

It is a cyclic number.

It is not a de Polignac number, because 671319709 - 2¹ = 671319707 is a prime.

Together with 671319707, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (671319707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335659854 + 335659855.

It is an arithmetic number, because the mean of its divisors is an integer number (335659855).

Almost surely, 2^671319709 is an apocalyptic number.

It is an amenable number.

671319709 is a deficient number, since it is larger than the sum of its proper divisors (1).

671319709 is an equidigital number, since it uses as much as digits as its factorization.

671319709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 71442, while the sum is 43.

The square root of 671319709 is about 25909.8380735967. The cubic root of 671319709 is about 875.6081579984.

The spelling of 671319709 in words is "six hundred seventy-one million, three hundred nineteen thousand, seven hundred nine".