6761166721 has 2 divisors, whose sum is σ = 6761166722. Its totient is φ = 6761166720.

The previous prime is 6761166719. The next prime is 6761166751. The reversal of 6761166721 is 1276611676.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6759306225 + 1860496 = 82215^2 + 1364^2 .

It is a cyclic number.

It is not a de Polignac number, because 6761166721 - 2¹ = 6761166719 is a prime.

Together with 6761166719, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (6761166751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3380583360 + 3380583361.

It is an arithmetic number, because the mean of its divisors is an integer number (3380583361).

Almost surely, 2^6761166721 is an apocalyptic number.

It is an amenable number.

6761166721 is a deficient number, since it is larger than the sum of its proper divisors (1).

6761166721 is an equidigital number, since it uses as much as digits as its factorization.

6761166721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 127008, while the sum is 43.

The square root of 6761166721 is about 82226.3140424037. The cubic root of 6761166721 is about 1890.9231626656.

The spelling of 6761166721 in words is "six billion, seven hundred sixty-one million, one hundred sixty-six thousand, seven hundred twenty-one".