6601661065 has 8 divisors (see below), whose sum is σ = 8195165640. Its totient is φ = 5099213952.

The previous prime is 6601661047. The next prime is 6601661111. The reversal of 6601661065 is 5601661066.

It can be written as a sum of positive squares in 4 ways, for example, as 2627997696 + 3973663369 = 51264^2 + 63037^2 .

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 6601661065 - 2⁹ = 6601660553 is a prime.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 22764204 + ... + 22764493.

It is an arithmetic number, because the mean of its divisors is an integer number (1024395705).

Almost surely, 2^6601661065 is an apocalyptic number.

It is an amenable number.

6601661065 is a deficient number, since it is larger than the sum of its proper divisors (1593504575).

6601661065 is a wasteful number, since it uses less digits than its factorization.

6601661065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45528731.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 6601661065 is about 81250.6065515821. The cubic root of 6601661065 is about 1875.9348052116.

Subtracting from 6601661065 its reverse (5601661066), we obtain a palindrome (999999999).

The spelling of 6601661065 in words is "six billion, six hundred one million, six hundred sixty-one thousand, sixty-five".