609691 has 4 divisors (see below), whose sum is σ = 641800. Its totient is φ = 577584.

The previous prime is 609683. The next prime is 609701. The reversal of 609691 is 196906.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 196906 = 2 ⋅98453.

It is a cyclic number.

It is not a de Polignac number, because 609691 - 2³ = 609683 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (609601) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 16026 + ... + 16063.

It is an arithmetic number, because the mean of its divisors is an integer number (160450).

2⁶⁰⁹⁶⁹¹ is an apocalyptic number.

609691 is a deficient number, since it is larger than the sum of its proper divisors (32109).

609691 is a wasteful number, since it uses less digits than its factorization.

609691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32108.

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

The square root of 609691 is about 780.8271255534. The cubic root of 609691 is about 84.7949382139.

The spelling of 609691 in words is "six hundred nine thousand, six hundred ninety-one".