660035561 has 8 divisors (see below), whose sum is σ = 663423048. Its totient is φ = 656656000.

The previous prime is 660035549. The next prime is 660035567. The reversal of 660035561 is 165530066.

It can be written as a sum of positive squares in 4 ways, for example, as 97397161 + 562638400 = 9869^2 + 23720^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-660035561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (660035567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 229271 + ... + 232131.

It is an arithmetic number, because the mean of its divisors is an integer number (82927881).

Almost surely, 2^660035561 is an apocalyptic number.

It is an amenable number.

660035561 is a deficient number, since it is larger than the sum of its proper divisors (3387487).

660035561 is a wasteful number, since it uses less digits than its factorization.

660035561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3963.

The product of its (nonzero) digits is 16200, while the sum is 32.

The square root of 660035561 is about 25691.1572530316. The cubic root of 660035561 is about 870.6744059560.

The spelling of 660035561 in words is "six hundred sixty million, thirty-five thousand, five hundred sixty-one".