660606689 has 8 divisors (see below), whose sum is σ = 723585960. Its totient is φ = 600307456.

The previous prime is 660606679. The next prime is 660606691. The reversal of 660606689 is 986606066.

It can be written as a sum of positive squares in 4 ways, for example, as 207129664 + 453477025 = 14392^2 + 21295^2 .

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 660606689 - 2⁸ = 660606433 is a prime.

It is not an unprimeable number, because it can be changed into a prime (660606619) 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, 669494 + ... + 670479.

It is an arithmetic number, because the mean of its divisors is an integer number (90448245).

Almost surely, 2^660606689 is an apocalyptic number.

It is an amenable number.

660606689 is a deficient number, since it is larger than the sum of its proper divisors (62979271).

660606689 is a wasteful number, since it uses less digits than its factorization.

660606689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1340019.

The product of its (nonzero) digits is 559872, while the sum is 47.

The square root of 660606689 is about 25702.2701137468. The cubic root of 660606689 is about 870.9254647384.

The spelling of 660606689 in words is "six hundred sixty million, six hundred six thousand, six hundred eighty-nine".