1821648800 has 36 divisors (see below), whose sum is σ = 4447102086. Its totient is φ = 728659200.

The previous prime is 1821648799. The next prime is 1821648809. The reversal of 1821648800 is 88461281.

It can be written as a sum of positive squares in 3 ways, for example, as 1746236944 + 75411856 = 41788^2 + 8684^2 .

It is not an unprimeable number, because it can be changed into a prime (1821648809) 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 5 ways as a sum of consecutive naturals, for example, 1137731 + ... + 1139330.

Almost surely, 2^1821648800 is an apocalyptic number.

1821648800 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1821648800 is an abundant number, since it is smaller than the sum of its proper divisors (2625453286).

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

1821648800 is a wasteful number, since it uses less digits than its factorization.

1821648800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2277081 (or 2277068 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 38.

The square root of 1821648800 is about 42680.7778748232. Note that the first 3 decimals coincide. The cubic root of 1821648800 is about 1221.2977322350.

The spelling of 1821648800 in words is "one billion, eight hundred twenty-one million, six hundred forty-eight thousand, eight hundred".