3661566761 has 4 divisors (see below), whose sum is σ = 3666604032. Its totient is φ = 3656529492.

The previous prime is 3661566751. The next prime is 3661566763. The reversal of 3661566761 is 1676651663.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 3661566761 - 2⁶ = 3661566697 is a prime.

It is a super-2 number, since 2×3661566761² = 26814142290520062242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3661566763) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2517545 + ... + 2518998.

It is an arithmetic number, because the mean of its divisors is an integer number (916651008).

Almost surely, 2^3661566761 is an apocalyptic number.

It is an amenable number.

3661566761 is a deficient number, since it is larger than the sum of its proper divisors (5037271).

3661566761 is an equidigital number, since it uses as much as digits as its factorization.

3661566761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5037270.

The product of its digits is 816480, while the sum is 47.

The square root of 3661566761 is about 60510.8813437716. The cubic root of 3661566761 is about 1541.3064139169.

The spelling of 3661566761 in words is "three billion, six hundred sixty-one million, five hundred sixty-six thousand, seven hundred sixty-one".