3691581 has 8 divisors (see below), whose sum is σ = 4936800. Its totient is φ = 2453712.

The previous prime is 3691577. The next prime is 3691603. The reversal of 3691581 is 1851963.

3691581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 3691581 - 2² = 3691577 is a prime.

It is a super-2 number, since 2×3691581² = 27255540559122, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3691531) 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 7 ways as a sum of consecutive naturals, for example, 531 + ... + 2768.

It is an arithmetic number, because the mean of its divisors is an integer number (617100).

Almost surely, 2^3691581 is an apocalyptic number.

It is an amenable number.

3691581 is a deficient number, since it is larger than the sum of its proper divisors (1245219).

3691581 is a wasteful number, since it uses less digits than its factorization.

3691581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3675.

The product of its digits is 6480, while the sum is 33.

The square root of 3691581 is about 1921.3487450226. The cubic root of 3691581 is about 154.5506374586.

The spelling of 3691581 in words is "three million, six hundred ninety-one thousand, five hundred eighty-one".