671605817 has 2 divisors, whose sum is σ = 671605818. Its totient is φ = 671605816.

The previous prime is 671605811. The next prime is 671605841. The reversal of 671605817 is 718506176.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 466084921 + 205520896 = 21589^2 + 14336^2 .

It is a cyclic number.

It is not a de Polignac number, because 671605817 - 2⁴ = 671605801 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (671605811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335802908 + 335802909.

It is an arithmetic number, because the mean of its divisors is an integer number (335802909).

Almost surely, 2^671605817 is an apocalyptic number.

It is an amenable number.

671605817 is a deficient number, since it is larger than the sum of its proper divisors (1).

671605817 is an equidigital number, since it uses as much as digits as its factorization.

671605817 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 70560, while the sum is 41.

The square root of 671605817 is about 25915.3587086886. The cubic root of 671605817 is about 875.7325313855.

The spelling of 671605817 in words is "six hundred seventy-one million, six hundred five thousand, eight hundred seventeen".