691069 has 4 divisors (see below), whose sum is σ = 702460. Its totient is φ = 679680.

The previous prime is 691063. The next prime is 691079. The reversal of 691069 is 960196.

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

It can be written as a sum of positive squares in 2 ways, for example, as 108900 + 582169 = 330^2 + 763^2 .

It is a cyclic number.

It is not a de Polignac number, because 691069 - 2⁵ = 691037 is a prime.

It is a super-2 number, since 2×691069² = 955152725522, which contains 22 as substring.

It is a Duffinian number.

691069 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 691069.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691063) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5604 + ... + 5725.

It is an arithmetic number, because the mean of its divisors is an integer number (175615).

2⁶⁹¹⁰⁶⁹ is an apocalyptic number.

It is an amenable number.

691069 is a deficient number, since it is larger than the sum of its proper divisors (11391).

691069 is a wasteful number, since it uses less digits than its factorization.

691069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11390.

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 691069 is about 831.3055996443. The cubic root of 691069 is about 88.4111698722.

The spelling of 691069 in words is "six hundred ninety-one thousand, sixty-nine".