13821500 has 96 divisors (see below), whose sum is σ = 37739520. Its totient is φ = 4296000.

The previous prime is 13821481. The next prime is 13821503. The reversal of 13821500 is 512831.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13821503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38321 + ... + 38679.

It is an arithmetic number, because the mean of its divisors is an integer number (393120).

Almost surely, 2^13821500 is an apocalyptic number.

13821500 is a gapful number since it is divisible by the number (10) 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 13821500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18869760).

13821500 is an abundant number, since it is smaller than the sum of its proper divisors (23918020).

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

13821500 is a wasteful number, since it uses less digits than its factorization.

13821500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 396 (or 384 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 13821500 is about 3717.7278006869. The cubic root of 13821500 is about 239.9855315352.

It can be divided in two parts, 1382 and 1500, that added together give a palindrome (2882).

The spelling of 13821500 in words is "thirteen million, eight hundred twenty-one thousand, five hundred".