6739561681 has 16 divisors (see below), whose sum is σ = 6915585600. Its totient is φ = 6565883968.

The previous prime is 6739561639. The next prime is 6739561723. The reversal of 6739561681 is 1861659376.

It is a happy number.

6739561681 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (6739561639) and next prime (6739561723).

It is a cyclic number.

It is not a de Polignac number, because 6739561681 - 2¹¹ = 6739559633 is a prime.

It is a super-2 number, since 2×6739561681² = 90843383304007091522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6739564681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3404550 + ... + 3406528.

It is an arithmetic number, because the mean of its divisors is an integer number (432224100).

Almost surely, 2^6739561681 is an apocalyptic number.

It is an amenable number.

6739561681 is a deficient number, since it is larger than the sum of its proper divisors (176023919).

6739561681 is a wasteful number, since it uses less digits than its factorization.

6739561681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2528.

The product of its digits is 1632960, while the sum is 52.

The square root of 6739561681 is about 82094.8334610650. The cubic root of 6739561681 is about 1888.9068901846.

The spelling of 6739561681 in words is "six billion, seven hundred thirty-nine million, five hundred sixty-one thousand, six hundred eighty-one".