691071 has 4 divisors (see below), whose sum is σ = 921432. Its totient is φ = 460712.

The previous prime is 691063. The next prime is 691079. The reversal of 691071 is 170196.

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

It is an interprime number because it is at equal distance from previous prime (691063) and next prime (691079).

It is a cyclic number.

It is not a de Polignac number, because 691071 - 2³ = 691063 is a prime.

It is a D-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 691071.

It is not an unprimeable number, because it can be changed into a prime (691079) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115176 + ... + 115181.

It is an arithmetic number, because the mean of its divisors is an integer number (230358).

2⁶⁹¹⁰⁷¹ is an apocalyptic number.

691071 is a deficient number, since it is larger than the sum of its proper divisors (230361).

691071 is a wasteful number, since it uses less digits than its factorization.

691071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230360.

The product of its (nonzero) digits is 378, while the sum is 24.

The square root of 691071 is about 831.3068025705. The cubic root of 691071 is about 88.4112551615.

The spelling of 691071 in words is "six hundred ninety-one thousand, seventy-one".