42090 has 32 divisors (see below), whose sum is σ = 107136. Its totient is φ = 10560.

The previous prime is 42089. The next prime is 42101. The reversal of 42090 is 9024.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a Curzon number.

It is a plaindrome in base 7.

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 42090.

It is an unprimeable 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, 660 + ... + 720.

It is an arithmetic number, because the mean of its divisors is an integer number (3348).

2⁴²⁰⁹⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53568).

42090 is an abundant number, since it is smaller than the sum of its proper divisors (65046).

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

42090 is a wasteful number, since it uses less digits than its factorization.

42090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94.

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 42090 is about 205.1584753307. The cubic root of 42090 is about 34.7850774969.

The spelling of 42090 in words is "forty-two thousand, ninety".