667871839 has 2 divisors, whose sum is σ = 667871840. Its totient is φ = 667871838.

The previous prime is 667871819. The next prime is 667871857. The reversal of 667871839 is 938178766.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 667871839 - 2⁵ = 667871807 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 667871839.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667871819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333935919 + 333935920.

It is an arithmetic number, because the mean of its divisors is an integer number (333935920).

Almost surely, 2^667871839 is an apocalyptic number.

667871839 is a deficient number, since it is larger than the sum of its proper divisors (1).

667871839 is an equidigital number, since it uses as much as digits as its factorization.

667871839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3048192, while the sum is 55.

The square root of 667871839 is about 25843.2164987255. The cubic root of 667871839 is about 874.1065553521.

The spelling of 667871839 in words is "six hundred sixty-seven million, eight hundred seventy-one thousand, eight hundred thirty-nine".