6391667 has 2 divisors, whose sum is σ = 6391668. Its totient is φ = 6391666.

The previous prime is 6391663. The next prime is 6391669. The reversal of 6391667 is 7661936.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6391667 - 2² = 6391663 is a prime.

Together with 6391669, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6391667.

It is not a weakly prime, because it can be changed into another prime (6391663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3195833 + 3195834.

It is an arithmetic number, because the mean of its divisors is an integer number (3195834).

Almost surely, 2^6391667 is an apocalyptic number.

6391667 is a deficient number, since it is larger than the sum of its proper divisors (1).

6391667 is an equidigital number, since it uses as much as digits as its factorization.

6391667 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40824, while the sum is 38.

The square root of 6391667 is about 2528.1746379552. The cubic root of 6391667 is about 185.5829384305.

The spelling of 6391667 in words is "six million, three hundred ninety-one thousand, six hundred sixty-seven".