66165 has 16 divisors (see below), whose sum is σ = 115776. Its totient is φ = 32000.

The previous prime is 66161. The next prime is 66169. The reversal of 66165 is 56166.

66165 = T₁₁₀ + T₁₁₁ + ... + T₁₁₉.

It is an interprime number because it is at equal distance from previous prime (66161) and next prime (66169).

It is not a de Polignac number, because 66165 - 2² = 66161 is a prime.

It is a Curzon number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 66165.

It is not an unprimeable number, because it can be changed into a prime (66161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36 + ... + 365.

It is an arithmetic number, because the mean of its divisors is an integer number (7236).

2⁶⁶¹⁶⁵ is an apocalyptic number.

It is an amenable number.

66165 is a deficient number, since it is larger than the sum of its proper divisors (49611).

66165 is a wasteful number, since it uses less digits than its factorization.

66165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 420.

The product of its digits is 1080, while the sum is 24.

The square root of 66165 is about 257.2255819315. The cubic root of 66165 is about 40.4460491811.

Subtracting from 66165 its reverse (56166), we obtain a palindrome (9999).

It can be divided in two parts, 66 and 165, that added together give a triangular number (231 = T₂₁).

The spelling of 66165 in words is "sixty-six thousand, one hundred sixty-five".