6819979 has 4 divisors (see below), whose sum is σ = 6827176. Its totient is φ = 6812784.

The previous prime is 6819977. The next prime is 6820001. The reversal of 6819979 is 9799186.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 9799186 = 2 ⋅4899593.

It is a cyclic number.

It is not a de Polignac number, because 6819979 - 2¹ = 6819977 is a prime.

It is a super-2 number, since 2×6819979² = 93024227120882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6819977) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1914 + ... + 4159.

It is an arithmetic number, because the mean of its divisors is an integer number (1706794).

Almost surely, 2^6819979 is an apocalyptic number.

6819979 is a deficient number, since it is larger than the sum of its proper divisors (7197).

6819979 is a wasteful number, since it uses less digits than its factorization.

6819979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7196.

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

The square root of 6819979 is about 2611.5089507792. The cubic root of 6819979 is about 189.6390098627.

The spelling of 6819979 in words is "six million, eight hundred nineteen thousand, nine hundred seventy-nine".