6677721613 has 2 divisors, whose sum is σ = 6677721614. Its totient is φ = 6677721612.

The previous prime is 6677721587. The next prime is 6677721623. The reversal of 6677721613 is 3161277766.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4419856324 + 2257865289 = 66482^2 + 47517^2 .

It is a cyclic number.

It is not a de Polignac number, because 6677721613 - 2²⁹ = 6140850701 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6677721623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3338860806 + 3338860807.

It is an arithmetic number, because the mean of its divisors is an integer number (3338860807).

Almost surely, 2^6677721613 is an apocalyptic number.

It is an amenable number.

6677721613 is a deficient number, since it is larger than the sum of its proper divisors (1).

6677721613 is an equidigital number, since it uses as much as digits as its factorization.

6677721613 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 444528, while the sum is 46.

The square root of 6677721613 is about 81717.3274954584. The cubic root of 6677721613 is about 1883.1117935422. Note that the first 3 decimals are identical.

The spelling of 6677721613 in words is "six billion, six hundred seventy-seven million, seven hundred twenty-one thousand, six hundred thirteen".