6777483871681 has 4 divisors (see below), whose sum is σ = 6778459196500. Its totient is φ = 6776508546864.

The previous prime is 6777483871667. The next prime is 6777483871693. The reversal of 6777483871681 is 1861783847776.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3996540748225 + 2780943123456 = 1999135^2 + 1667616^2 .

It is a cyclic number.

It is not a de Polignac number, because 6777483871681 - 2⁷ = 6777483871553 is a prime.

It is a super-2 number, since 2×6777483871681² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6777483871981) 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, 487651986 + ... + 487665883.

It is an arithmetic number, because the mean of its divisors is an integer number (1694614799125).

Almost surely, 2^{6777483871681} is an apocalyptic number.

It is an amenable number.

6777483871681 is a deficient number, since it is larger than the sum of its proper divisors (975324819).

6777483871681 is an equidigital number, since it uses as much as digits as its factorization.

6777483871681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 975324818.

The product of its digits is 531062784, while the sum is 73.

The spelling of 6777483871681 in words is "six trillion, seven hundred seventy-seven billion, four hundred eighty-three million, eight hundred seventy-one thousand, six hundred eighty-one".