28140 has 48 divisors (see below), whose sum is σ = 91392. Its totient is φ = 6336.

The previous prime is 28123. The next prime is 28151. The reversal of 28140 is 4182.

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

It is a nialpdrome in base 15.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 387 + ... + 453.

It is an arithmetic number, because the mean of its divisors is an integer number (1904).

2²⁸¹⁴⁰ is an apocalyptic number.

28140 is a gapful number since it is divisible by the number (20) 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 28140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45696).

28140 is an abundant number, since it is smaller than the sum of its proper divisors (63252).

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

28140 is a wasteful number, since it uses less digits than its factorization.

28140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86 (or 84 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 28140 is about 167.7498137108. The cubic root of 28140 is about 30.4164154188.

The spelling of 28140 in words is "twenty-eight thousand, one hundred forty".