20142 has 16 divisors (see below), whose sum is σ = 44880. Its totient is φ = 6696.

The previous prime is 20129. The next prime is 20143. The reversal of 20142 is 24102.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20143) by changing a digit.

20142 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 133 + ... + 240.

It is an arithmetic number, because the mean of its divisors is an integer number (2805).

2²⁰¹⁴² is an apocalyptic number.

20142 is an abundant number, since it is smaller than the sum of its proper divisors (24738).

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 (22440).

20142 is a wasteful number, since it uses less digits than its factorization.

20142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384 (or 378 counting only the distinct ones).

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

The square root of 20142 is about 141.9225140702. The cubic root of 20142 is about 27.2082659422.

Adding to 20142 its reverse (24102), we get a palindrome (44244).

It can be divided in two parts, 2014 and 2, that added together give a triangular number (2016 = T₆₃).

The spelling of 20142 in words is "twenty thousand, one hundred forty-two", and thus it is an iban number.