6691831 has 4 divisors (see below), whose sum is σ = 6697600. Its totient is φ = 6686064.

The previous prime is 6691801. The next prime is 6691843. The reversal of 6691831 is 1381966.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 6691831 - 2⁵ = 6691799 is a prime.

It is a super-2 number, since 2×6691831² = 89561204265122, which 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 (6691801) 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, 471 + ... + 3688.

It is an arithmetic number, because the mean of its divisors is an integer number (1674400).

Almost surely, 2^6691831 is an apocalyptic number.

6691831 is a deficient number, since it is larger than the sum of its proper divisors (5769).

6691831 is a wasteful number, since it uses less digits than its factorization.

6691831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5768.

The product of its digits is 7776, while the sum is 34.

The square root of 6691831 is about 2586.8573598094. The cubic root of 6691831 is about 188.4437138900.

It can be divided in two parts, 669 and 1831, that added together give a square (2500 = 50²).

The spelling of 6691831 in words is "six million, six hundred ninety-one thousand, eight hundred thirty-one".