691596 has 18 divisors (see below), whose sum is σ = 1748292. Its totient is φ = 230520.

The previous prime is 691591. The next prime is 691631. The reversal of 691596 is 695196.

691596 is a `hidden beast` number, since 69 + 1 + 596 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 19211 = 691596 / (6 + 9 + 1 + 5 + 9 + 6).

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 691596.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 691596.

It is not an unprimeable number, because it can be changed into a prime (691591) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9570 + ... + 9641.

2⁶⁹¹⁵⁹⁶ is an apocalyptic number.

It is an amenable number.

691596 is an abundant number, since it is smaller than the sum of its proper divisors (1056696).

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

691596 is a wasteful number, since it uses less digits than its factorization.

691596 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19221 (or 19216 counting only the distinct ones).

The product of its digits is 14580, while the sum is 36.

The square root of 691596 is about 831.6225105178. The cubic root of 691596 is about 88.4336378882.

Subtracting 691596 from its reverse (695196), we obtain a square (3600 = 60²).

The spelling of 691596 in words is "six hundred ninety-one thousand, five hundred ninety-six".