691608 has 16 divisors (see below), whose sum is σ = 1729080. Its totient is φ = 230528.

The previous prime is 691591. The next prime is 691631. The reversal of 691608 is 806196.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 691608.

It is an unprimeable number.

691608 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14385 + ... + 14432.

2⁶⁹¹⁶⁰⁸ is an apocalyptic number.

It is an amenable number.

691608 is an abundant number, since it is smaller than the sum of its proper divisors (1037472).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

691608 is a wasteful number, since it uses less digits than its factorization.

691608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28826 (or 28822 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 691608 is about 831.6297252985. The cubic root of 691608 is about 88.4341493609.

The spelling of 691608 in words is "six hundred ninety-one thousand, six hundred eight".