42660 has 48 divisors (see below), whose sum is σ = 134400. Its totient is φ = 11232.

The previous prime is 42649. The next prime is 42667. The reversal of 42660 is 6624.

Added to its reverse (6624) it gives a square (49284 = 222²).

42660 is a `hidden beast` number, since 4 + 2 + 660 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nialpdrome in base 15.

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 42660.

It is not an unprimeable number, because it can be changed into a prime (42667) by changing a digit.

42660 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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, 501 + ... + 579.

It is an arithmetic number, because the mean of its divisors is an integer number (2800).

2⁴²⁶⁶⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67200).

42660 is an abundant number, since it is smaller than the sum of its proper divisors (91740).

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

42660 is a wasteful number, since it uses less digits than its factorization.

42660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97 (or 89 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 42660 is about 206.5429737367. The cubic root of 42660 is about 34.9413985354.

Adding to 42660 its reverse (6624), we get a square (49284 = 222²).

The spelling of 42660 in words is "forty-two thousand, six hundred sixty".