42120 has 80 divisors (see below), whose sum is σ = 152460. Its totient is φ = 10368.

The previous prime is 42101. The next prime is 42131. The reversal of 42120 is 2124.

It can be written as a sum of positive squares in 2 ways, for example, as 39204 + 2916 = 198^2 + 54^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a nialpdrome in base 15.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 42120.

It is an unprimeable number.

42120 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 (5) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3234 + ... + 3246.

2⁴²¹²⁰ is an apocalyptic number.

42120 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76230).

42120 is an abundant number, since it is smaller than the sum of its proper divisors (110340).

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

42120 is a wasteful number, since it uses less digits than its factorization.

42120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36 (or 23 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 42120 is about 205.2315765178. The cubic root of 42120 is about 34.7933399859.

Adding to 42120 its reverse (2124), we get a palindrome (44244).

It can be divided in two parts, 421 and 20, that added together give a square (441 = 21²).

The spelling of 42120 in words is "forty-two thousand, one hundred twenty", and thus it is an iban number.