6689731 has 4 divisors (see below), whose sum is σ = 6701464. Its totient is φ = 6678000.

The previous prime is 6689723. The next prime is 6689741. The reversal of 6689731 is 1379866.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6689731 - 2³ = 6689723 is a prime.

It is a super-2 number, since 2×6689731² = 89505001704722, which contains 22 as substring.

It is a Duffinian number.

6689731 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (6689701) 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, 4965 + ... + 6166.

It is an arithmetic number, because the mean of its divisors is an integer number (1675366).

Almost surely, 2^6689731 is an apocalyptic number.

6689731 is a deficient number, since it is larger than the sum of its proper divisors (11733).

6689731 is a wasteful number, since it uses less digits than its factorization.

6689731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11732.

The product of its digits is 54432, while the sum is 40.

The square root of 6689731 is about 2586.4514300485. The cubic root of 6689731 is about 188.4239996443.

The spelling of 6689731 in words is "six million, six hundred eighty-nine thousand, seven hundred thirty-one".