3691609 has 4 divisors (see below), whose sum is σ = 3761316. Its totient is φ = 3621904.

The previous prime is 3691603. The next prime is 3691619. The reversal of 3691609 is 9061963.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9061963 = 151 ⋅60013.

It can be written as a sum of positive squares in 2 ways, for example, as 3229209 + 462400 = 1797^2 + 680^2 .

It is a cyclic number.

It is not a de Polignac number, because 3691609 - 2⁵ = 3691577 is a prime.

It is a super-3 number, since 3×3691609³ (a number of 21 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3691603) 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, 34774 + ... + 34879.

It is an arithmetic number, because the mean of its divisors is an integer number (940329).

Almost surely, 2^3691609 is an apocalyptic number.

It is an amenable number.

3691609 is a deficient number, since it is larger than the sum of its proper divisors (69707).

3691609 is an equidigital number, since it uses as much as digits as its factorization.

3691609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69706.

The product of its (nonzero) digits is 8748, while the sum is 34.

The square root of 3691609 is about 1921.3560315569. The cubic root of 3691609 is about 154.5510282041.

The spelling of 3691609 in words is "three million, six hundred ninety-one thousand, six hundred nine".