1820644800 has 336 divisors, whose sum is σ = 6508333440. Its totient is φ = 442920960.

The previous prime is 1820644769. The next prime is 1820644843. The reversal of 1820644800 is 84460281.

It is a super-3 number, since 3×1820644800³ (a number of 29 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 10171111 + ... + 10171289.

It is an arithmetic number, because the mean of its divisors is an integer number (19370040).

Almost surely, 2^1820644800 is an apocalyptic number.

1820644800 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 1820644800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3254166720).

1820644800 is an abundant number, since it is smaller than the sum of its proper divisors (4687688640).

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

1820644800 is a wasteful number, since it uses less digits than its factorization.

1820644800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 380 (or 365 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 33.

The square root of 1820644800 is about 42669.0145187348. The cubic root of 1820644800 is about 1221.0733186411.

The spelling of 1820644800 in words is "one billion, eight hundred twenty million, six hundred forty-four thousand, eight hundred".