66945 has 8 divisors (see below), whose sum is σ = 107136. Its totient is φ = 35696.

The previous prime is 66943. The next prime is 66947. The reversal of 66945 is 54966.

It is an interprime number because it is at equal distance from previous prime (66943) and next prime (66947).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66945 - 2¹ = 66943 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2217 + ... + 2246.

It is an arithmetic number, because the mean of its divisors is an integer number (13392).

2⁶⁶⁹⁴⁵ is an apocalyptic number.

It is an amenable number.

66945 is a deficient number, since it is larger than the sum of its proper divisors (40191).

66945 is a wasteful number, since it uses less digits than its factorization.

66945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4471.

The product of its digits is 6480, while the sum is 30.

The square root of 66945 is about 258.7373185298. The cubic root of 66945 is about 40.6043642732.

The spelling of 66945 in words is "sixty-six thousand, nine hundred forty-five".