3565555661 has 2 divisors, whose sum is σ = 3565555662. Its totient is φ = 3565555660.

The previous prime is 3565555649. The next prime is 3565555667. The reversal of 3565555661 is 1665555653.

3565555661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2143134436 + 1422421225 = 46294^2 + 37715^2 .

It is an emirp because it is prime and its reverse (1665555653) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3565555661 - 2¹⁴ = 3565539277 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3565555667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1782777830 + 1782777831.

It is an arithmetic number, because the mean of its divisors is an integer number (1782777831).

Almost surely, 2^3565555661 is an apocalyptic number.

It is an amenable number.

3565555661 is a deficient number, since it is larger than the sum of its proper divisors (1).

3565555661 is an equidigital number, since it uses as much as digits as its factorization.

3565555661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2025000, while the sum is 47.

The square root of 3565555661 is about 59712.2739560302. The cubic root of 3565555661 is about 1527.7152252308.

The spelling of 3565555661 in words is "three billion, five hundred sixty-five million, five hundred fifty-five thousand, six hundred sixty-one".