665560615 has 4 divisors (see below), whose sum is σ = 798672744. Its totient is φ = 532448488.

The previous prime is 665560589. The next prime is 665560627. The reversal of 665560615 is 516065566.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 665560615 - 2⁷ = 665560487 is a prime.

It is a Duffinian number.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 66556057 + ... + 66556066.

It is an arithmetic number, because the mean of its divisors is an integer number (199668186).

Almost surely, 2^665560615 is an apocalyptic number.

665560615 is a deficient number, since it is larger than the sum of its proper divisors (133112129).

665560615 is a wasteful number, since it uses less digits than its factorization.

665560615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133112128.

The product of its (nonzero) digits is 162000, while the sum is 40.

The square root of 665560615 is about 25798.4614851351. The cubic root of 665560615 is about 873.0970847515.

The spelling of 665560615 in words is "six hundred sixty-five million, five hundred sixty thousand, six hundred fifteen".