1821288 has 64 divisors (see below), whose sum is σ = 5362560. Its totient is φ = 504576.

The previous prime is 1821263. The next prime is 1821289. The reversal of 1821288 is 8821281.

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

It is not an unprimeable number, because it can be changed into a prime (1821289) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 6070 + ... + 6362.

It is an arithmetic number, because the mean of its divisors is an integer number (83790).

2^1821288 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 1821288, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2681280).

1821288 is an abundant number, since it is smaller than the sum of its proper divisors (3541272).

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

1821288 is a wasteful number, since it uses less digits than its factorization.

1821288 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346 (or 342 counting only the distinct ones).

The product of its digits is 2048, while the sum is 30.

The square root of 1821288 is about 1349.5510364562. The cubic root of 1821288 is about 122.1217095888.

The spelling of 1821288 in words is "one million, eight hundred twenty-one thousand, two hundred eighty-eight".