15420 has 24 divisors (see below), whose sum is σ = 43344.
Its totient is φ = 4096.
The previous prime is 15413. The next prime is 15427. The reversal of 15420 is 2451.
Adding to 15420 its reverse (2451), we get a palindrome (17871).
It can be divided in two parts, 15 and 420, that added together give a triangular number (435 = T29).
It is an interprime number because it is at equal distance from previous prime (15413) and next prime (15427).
It is a Harshad number since it is a multiple of its sum of digits (12).
15420 is an undulating number in base 16.
It is a zygodrome in base 2.
It is a junction number, because it is equal to n+sod(n) for n = 15396 and 15405.
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 15420.
It is not an unprimeable number, because it can be changed into a prime (15427) by changing a digit.
15420 is an untouchable number, because it is not equal to the sum of proper divisors of any number.
In principle, a polygon with 15420 sides can be constructed with ruler and compass.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69 + ... + 188.
It is an arithmetic number, because the mean of its divisors is an integer number (1806).
215420 is an apocalyptic number.
15420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.
It is an amenable number.
15420 is an abundant number, since it is smaller than the sum of its proper divisors (27924).
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 (21672).
15420 is a wasteful number, since it uses less digits than its factorization.
15420 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 269 (or 267 counting only the distinct ones).
The product of its (nonzero) digits is 40, while the sum is 12.
The square root of 15420 is about 124.1772926102.
The cubic root of 15420 is about 24.8901849996.
The spelling of 15420 in words is "fifteen thousand, four hundred twenty".