66665305 has 16 divisors (see below), whose sum is σ = 93899520. Its totient is φ = 44476992.

The previous prime is 66665273. The next prime is 66665311. The reversal of 66665305 is 50356666.

It is a happy number.

It is not a de Polignac number, because 66665305 - 2⁵ = 66665273 is a prime.

It is a super-3 number, since 3×66665305³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

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, 24445 + ... + 27034.

It is an arithmetic number, because the mean of its divisors is an integer number (5868720).

Almost surely, 2^66665305 is an apocalyptic number.

It is an amenable number.

66665305 is a deficient number, since it is larger than the sum of its proper divisors (27234215).

66665305 is a wasteful number, since it uses less digits than its factorization.

66665305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51528.

The product of its (nonzero) digits is 97200, while the sum is 37.

The square root of 66665305 is about 8164.8824241381. The cubic root of 66665305 is about 405.4773723755.

The spelling of 66665305 in words is "sixty-six million, six hundred sixty-five thousand, three hundred five".