6699879509 has 2 divisors, whose sum is σ = 6699879510. Its totient is φ = 6699879508.

The previous prime is 6699879499. The next prime is 6699879517. The reversal of 6699879509 is 9059789966.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5799279409 + 900600100 = 76153^2 + 30010^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6699879509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6699879409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3349939754 + 3349939755.

It is an arithmetic number, because the mean of its divisors is an integer number (3349939755).

Almost surely, 2^6699879509 is an apocalyptic number.

It is an amenable number.

6699879509 is a deficient number, since it is larger than the sum of its proper divisors (1).

6699879509 is an equidigital number, since it uses as much as digits as its factorization.

6699879509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 66134880, while the sum is 68.

The square root of 6699879509 is about 81852.7916994894. The cubic root of 6699879509 is about 1885.1923299547.

The spelling of 6699879509 in words is "six billion, six hundred ninety-nine million, eight hundred seventy-nine thousand, five hundred nine".