1821384 has 48 divisors (see below), whose sum is σ = 5061420. Its totient is φ = 591360.

The previous prime is 1821377. The next prime is 1821401. The reversal of 1821384 is 4831281.

It can be written as a sum of positive squares in 2 ways, for example, as 1258884 + 562500 = 1122^2 + 750^2 .

It is a nude number because it is divisible by every one of its digits.

It is a plaindrome in base 14.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2644 + ... + 3260.

2^1821384 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1821384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2530710).

1821384 is an abundant number, since it is smaller than the sum of its proper divisors (3240036).

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

1821384 is a wasteful number, since it uses less digits than its factorization.

1821384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 670 (or 663 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 1821384 is about 1349.5866033716. The cubic root of 1821384 is about 122.1238552275.

The spelling of 1821384 in words is "one million, eight hundred twenty-one thousand, three hundred eighty-four".