660551565 has 32 divisors (see below), whose sum is σ = 1120490496. Its totient is φ = 331706880.

The previous prime is 660551543. The next prime is 660551579. The reversal of 660551565 is 565155066.

It is not a de Polignac number, because 660551565 - 2⁶ = 660551501 is a prime.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 1992 + ... + 36401.

It is an arithmetic number, because the mean of its divisors is an integer number (35015328).

Almost surely, 2^660551565 is an apocalyptic number.

It is an amenable number.

660551565 is a deficient number, since it is larger than the sum of its proper divisors (459938931).

660551565 is a wasteful number, since it uses less digits than its factorization.

660551565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38469.

The product of its (nonzero) digits is 135000, while the sum is 39.

The square root of 660551565 is about 25701.1977347360. The cubic root of 660551565 is about 870.9012394157.

The spelling of 660551565 in words is "six hundred sixty million, five hundred fifty-one thousand, five hundred sixty-five".