64216665 has 16 divisors (see below), whose sum is σ = 114163200. Its totient is φ = 34248816.

The previous prime is 64216639. The next prime is 64216679. The reversal of 64216665 is 56661246.

It is a happy number.

It is not a de Polignac number, because 64216665 - 2⁶ = 64216601 is a prime.

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, 237705 + ... + 237974.

It is an arithmetic number, because the mean of its divisors is an integer number (7135200).

Almost surely, 2^64216665 is an apocalyptic number.

It is an amenable number.

64216665 is a deficient number, since it is larger than the sum of its proper divisors (49946535).

64216665 is a wasteful number, since it uses less digits than its factorization.

64216665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 475693 (or 475687 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The square root of 64216665 is about 8013.5301209891. The cubic root of 64216665 is about 400.4508770005.

The spelling of 64216665 in words is "sixty-four million, two hundred sixteen thousand, six hundred sixty-five".