691868 has 12 divisors (see below), whose sum is σ = 1217160. Its totient is φ = 344112.

The previous prime is 691843. The next prime is 691871. The reversal of 691868 is 868196.

691868 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 755 + ... + 1397.

It is an arithmetic number, because the mean of its divisors is an integer number (101430).

2⁶⁹¹⁸⁶⁸ is an apocalyptic number.

It is an amenable number.

691868 is a deficient number, since it is larger than the sum of its proper divisors (525292).

691868 is a wasteful number, since it uses less digits than its factorization.

691868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 916 (or 914 counting only the distinct ones).

The product of its digits is 20736, while the sum is 38.

The square root of 691868 is about 831.7860301784. The cubic root of 691868 is about 88.4452298179.

The spelling of 691868 in words is "six hundred ninety-one thousand, eight hundred sixty-eight".