691000 has 32 divisors (see below), whose sum is σ = 1619280. Its totient is φ = 276000.

The previous prime is 690997. The next prime is 691001. The reversal of 691000 is 196.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 655 + ... + 1345.

2⁶⁹¹⁰⁰⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 691000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (809640).

691000 is an abundant number, since it is smaller than the sum of its proper divisors (928280).

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

691000 is a wasteful number, since it uses less digits than its factorization.

691000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 712 (or 698 counting only the distinct ones).

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 691000 is about 831.2640976248. The cubic root of 691000 is about 88.4082272940.

Adding to 691000 its reverse (196), we get a palindrome (691196).

The spelling of 691000 in words is "six hundred ninety-one thousand".