3661831809 has 6 divisors (see below), whose sum is σ = 5289312626. Its totient is φ = 2441221200.

The previous prime is 3661831801. The next prime is 3661831813. The reversal of 3661831809 is 9081381663.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 3528360000 + 133471809 = 59400^2 + 11553^2 .

It is not a de Polignac number, because 3661831809 - 2³ = 3661831801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3661831801) 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, 203435092 + ... + 203435109.

Almost surely, 2^3661831809 is an apocalyptic number.

It is an amenable number.

3661831809 is a deficient number, since it is larger than the sum of its proper divisors (1627480817).

3661831809 is a wasteful number, since it uses less digits than its factorization.

3661831809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 406870207 (or 406870204 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 3661831809 is about 60513.0713895766. The cubic root of 3661831809 is about 1541.3436029449.

The spelling of 3661831809 in words is "three billion, six hundred sixty-one million, eight hundred thirty-one thousand, eight hundred nine".