66885 has 32 divisors (see below), whose sum is σ = 134400. Its totient is φ = 28224.

The previous prime is 66883. The next prime is 66889. The reversal of 66885 is 58866.

Added to its reverse (58866) it gives a triangular number (125751 = T₅₀₁).

It is not a de Polignac number, because 66885 - 2¹ = 66883 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is a plaindrome in base 9.

It is a zygodrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66883) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5139 + ... + 5151.

It is an arithmetic number, because the mean of its divisors is an integer number (4200).

2⁶⁶⁸⁸⁵ is an apocalyptic number.

66885 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66885 is an abundant number, since it is smaller than the sum of its proper divisors (67515).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67200).

66885 is a wasteful number, since it uses less digits than its factorization.

66885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42 (or 28 counting only the distinct ones).

The product of its digits is 11520, while the sum is 33.

The square root of 66885 is about 258.6213448268. The cubic root of 66885 is about 40.5922299835.

Adding to 66885 its reverse (58866), we get a triangular number (125751 = T₅₀₁).

The spelling of 66885 in words is "sixty-six thousand, eight hundred eighty-five".