6891979 has 2 divisors, whose sum is σ = 6891980. Its totient is φ = 6891978.

The previous prime is 6891971. The next prime is 6891991. The reversal of 6891979 is 9791986.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6891979 - 2³ = 6891971 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (6891971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3445989 + 3445990.

It is an arithmetic number, because the mean of its divisors is an integer number (3445990).

Almost surely, 2^6891979 is an apocalyptic number.

6891979 is a deficient number, since it is larger than the sum of its proper divisors (1).

6891979 is an equidigital number, since it uses as much as digits as its factorization.

6891979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 244944, while the sum is 49.

The square root of 6891979 is about 2625.2578920937. The cubic root of 6891979 is about 190.3040284848.

The spelling of 6891979 in words is "six million, eight hundred ninety-one thousand, nine hundred seventy-nine".