4515561661 has 8 divisors (see below), whose sum is σ = 4942633304. Its totient is φ = 4099878720.

The previous prime is 4515561653. The next prime is 4515561671. The reversal of 4515561661 is 1661655154.

It can be written as a sum of positive squares in 4 ways, for example, as 461820100 + 4053741561 = 21490^2 + 63669^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 4515561661 - 2³ = 4515561653 is a prime.

It is a super-2 number, since 2×4515561661² = 40780594228586157842, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4515561601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2846346 + ... + 2847931.

It is an arithmetic number, because the mean of its divisors is an integer number (617829163).

Almost surely, 2^4515561661 is an apocalyptic number.

It is an amenable number.

4515561661 is a deficient number, since it is larger than the sum of its proper divisors (427071643).

4515561661 is a wasteful number, since it uses less digits than its factorization.

4515561661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5694351.

The product of its digits is 108000, while the sum is 40.

The square root of 4515561661 is about 67197.9289933849. The cubic root of 4515561661 is about 1652.8645265026.

The spelling of 4515561661 in words is "four billion, five hundred fifteen million, five hundred sixty-one thousand, six hundred sixty-one".