671998693 has 2 divisors, whose sum is σ = 671998694. Its totient is φ = 671998692.

The previous prime is 671998609. The next prime is 671998703. The reversal of 671998693 is 396899176.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 361076004 + 310922689 = 19002^2 + 17633^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-671998693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (671998603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335999346 + 335999347.

It is an arithmetic number, because the mean of its divisors is an integer number (335999347).

Almost surely, 2^671998693 is an apocalyptic number.

It is an amenable number.

671998693 is a deficient number, since it is larger than the sum of its proper divisors (1).

671998693 is an equidigital number, since it uses as much as digits as its factorization.

671998693 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4408992, while the sum is 58.

The square root of 671998693 is about 25922.9375843094. The cubic root of 671998693 is about 875.9032601169.

The spelling of 671998693 in words is "six hundred seventy-one million, nine hundred ninety-eight thousand, six hundred ninety-three".