6691745 has 4 divisors (see below), whose sum is σ = 8030100. Its totient is φ = 5353392.

The previous prime is 6691723. The next prime is 6691771. The reversal of 6691745 is 5471966.

6691745 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5471966 = 2 ⋅2735983.

It can be written as a sum of positive squares in 2 ways, for example, as 1597696 + 5094049 = 1264^2 + 2257^2 .

It is a cyclic number.

It is not a de Polignac number, because 6691745 - 2¹⁰ = 6690721 is a prime.

It is a super-2 number, since 2×6691745² = 89558902290050, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 6691699 and 6691708.

It is an unprimeable number.

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, 669170 + ... + 669179.

It is an arithmetic number, because the mean of its divisors is an integer number (2007525).

Almost surely, 2^6691745 is an apocalyptic number.

It is an amenable number.

6691745 is a deficient number, since it is larger than the sum of its proper divisors (1338355).

6691745 is a wasteful number, since it uses less digits than its factorization.

6691745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1338354.

The product of its digits is 45360, while the sum is 38.

The square root of 6691745 is about 2586.8407372701. The cubic root of 6691745 is about 188.4429066257.

The spelling of 6691745 in words is "six million, six hundred ninety-one thousand, seven hundred forty-five".