6991246109 has 2 divisors, whose sum is σ = 6991246110. Its totient is φ = 6991246108.

The previous prime is 6991246063. The next prime is 6991246177. The reversal of 6991246109 is 9016421996.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3687525625 + 3303720484 = 60725^2 + 57478^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6991246109 is a prime.

It is a super-3 number, since 3×6991246109³ (a number of 31 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6991246609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3495623054 + 3495623055.

It is an arithmetic number, because the mean of its divisors is an integer number (3495623055).

Almost surely, 2^6991246109 is an apocalyptic number.

It is an amenable number.

6991246109 is a deficient number, since it is larger than the sum of its proper divisors (1).

6991246109 is an equidigital number, since it uses as much as digits as its factorization.

6991246109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 209952, while the sum is 47.

The square root of 6991246109 is about 83613.6717827892. The cubic root of 6991246109 is about 1912.1334410414.

The spelling of 6991246109 in words is "six billion, nine hundred ninety-one million, two hundred forty-six thousand, one hundred nine".