660666745 has 16 divisors (see below), whose sum is σ = 804070800. Its totient is φ = 521073664.

The previous prime is 660666707. The next prime is 660666751. The reversal of 660666745 is 547666066.

It can be written as a sum of positive squares in 8 ways, for example, as 107993664 + 552673081 = 10392^2 + 23509^2 .

It is a cyclic number.

It is not a de Polignac number, because 660666745 - 2¹⁵ = 660633977 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 660666695 and 660666704.

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 15 ways as a sum of consecutive naturals, for example, 98829 + ... + 105301.

It is an arithmetic number, because the mean of its divisors is an integer number (50254425).

Almost surely, 2^660666745 is an apocalyptic number.

It is an amenable number.

660666745 is a deficient number, since it is larger than the sum of its proper divisors (143404055).

660666745 is a wasteful number, since it uses less digits than its factorization.

660666745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6764.

The product of its (nonzero) digits is 1088640, while the sum is 46.

The square root of 660666745 is about 25703.4383886670. The cubic root of 660666745 is about 870.9518559914.

The spelling of 660666745 in words is "six hundred sixty million, six hundred sixty-six thousand, seven hundred forty-five".