665170681615 has 16 divisors (see below), whose sum is σ = 871198623360. Its totient is φ = 483521756320.

The previous prime is 665170681603. The next prime is 665170681663. The reversal of 665170681615 is 516186071566.

It is a happy number.

It is not a de Polignac number, because 665170681615 - 2²¹ = 665168584463 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 (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2871745 + ... + 3094714.

It is an arithmetic number, because the mean of its divisors is an integer number (54449913960).

Almost surely, 2^665170681615 is an apocalyptic number.

665170681615 is a deficient number, since it is larger than the sum of its proper divisors (206027941745).

665170681615 is a wasteful number, since it uses less digits than its factorization.

665170681615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5968502.

The product of its (nonzero) digits is 1814400, while the sum is 52.

The spelling of 665170681615 in words is "six hundred sixty-five billion, one hundred seventy million, six hundred eighty-one thousand, six hundred fifteen".