1821600 has 216 divisors, whose sum is σ = 7312032. Its totient is φ = 422400.

The previous prime is 1821583. The next prime is 1821613. The reversal of 1821600 is 61281.

It is a Harshad number since it is a multiple of its sum of digits (18).

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 35 ways as a sum of consecutive naturals, for example, 79189 + ... + 79211.

It is an arithmetic number, because the mean of its divisors is an integer number (33852).

2^1821600 is an apocalyptic number.

1821600 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 1821600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3656016).

1821600 is an abundant number, since it is smaller than the sum of its proper divisors (5490432).

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

1821600 is a wasteful number, since it uses less digits than its factorization.

1821600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60 (or 44 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 1821600 is about 1349.6666255042. Note that the first 4 decimals coincide. The cubic root of 1821600 is about 122.1286826389.

Adding to 1821600 its reverse (61281), we get a palindrome (1882881).

The spelling of 1821600 in words is "one million, eight hundred twenty-one thousand, six hundred".