6691729 has 4 divisors (see below), whose sum is σ = 7300080. Its totient is φ = 6083380.

The previous prime is 6691723. The next prime is 6691771. The reversal of 6691729 is 9271966.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6691729 - 2⁵ = 6691697 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6691691 and 6691700.

It is not an unprimeable number, because it can be changed into a prime (6691723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 304159 + ... + 304180.

It is an arithmetic number, because the mean of its divisors is an integer number (1825020).

Almost surely, 2^6691729 is an apocalyptic number.

It is an amenable number.

6691729 is a deficient number, since it is larger than the sum of its proper divisors (608351).

6691729 is a wasteful number, since it uses less digits than its factorization.

6691729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 608350.

The product of its digits is 40824, while the sum is 40.

The square root of 6691729 is about 2586.8376446928. The cubic root of 6691729 is about 188.4427564362.

The spelling of 6691729 in words is "six million, six hundred ninety-one thousand, seven hundred twenty-nine".