691158 has 16 divisors (see below), whose sum is σ = 1488816. Its totient is φ = 212640.

The previous prime is 691153. The next prime is 691181. The reversal of 691158 is 851196.

It is a happy number.

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 691158.

It is not an unprimeable number, because it can be changed into a prime (691151) by changing a digit.

691158 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 7 ways as a sum of consecutive naturals, for example, 4353 + ... + 4508.

It is an arithmetic number, because the mean of its divisors is an integer number (93051).

2⁶⁹¹¹⁵⁸ is an apocalyptic number.

691158 is an abundant number, since it is smaller than the sum of its proper divisors (797658).

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

691158 is a wasteful number, since it uses less digits than its factorization.

691158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8879.

The product of its digits is 2160, while the sum is 30.

The square root of 691158 is about 831.3591281751. The cubic root of 691158 is about 88.4149650824.

The spelling of 691158 in words is "six hundred ninety-one thousand, one hundred fifty-eight".