6881312731669 has 4 divisors (see below), whose sum is σ = 6882577451820. Its totient is φ = 6880048011520.

The previous prime is 6881312731663. The next prime is 6881312731673. The reversal of 6881312731669 is 9661372131886.

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 4691179123569 + 2190133608100 = 2165913^2 + 1479910^2 .

It is a cyclic number.

It is not a de Polignac number, because 6881312731669 - 2⁹ = 6881312731157 is a prime.

It is a super-2 number, since 2×6881312731669² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6881312731663) 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 in 3 ways as a sum of consecutive naturals, for example, 632351914 + ... + 632362795.

It is an arithmetic number, because the mean of its divisors is an integer number (1720644362955).

Almost surely, 2^{6881312731669} is an apocalyptic number.

It is an amenable number.

6881312731669 is a deficient number, since it is larger than the sum of its proper divisors (1264720151).

6881312731669 is a wasteful number, since it uses less digits than its factorization.

6881312731669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1264720150.

The product of its digits is 15676416, while the sum is 61.

The spelling of 6881312731669 in words is "six trillion, eight hundred eighty-one billion, three hundred twelve million, seven hundred thirty-one thousand, six hundred sixty-nine".