1921800384 has 168 divisors, whose sum is σ = 6572432880. Its totient is φ = 549061632.

The previous prime is 1921800347. The next prime is 1921800389. The reversal of 1921800384 is 4830081291.

It is a tau number, because it is divible by the number of its divisors (168).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (1921800389) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 73324 + ... + 96020.

Almost surely, 2^1921800384 is an apocalyptic number.

1921800384 is a gapful number since it is divisible by the number (14) 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 1921800384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3286216440).

1921800384 is an abundant number, since it is smaller than the sum of its proper divisors (4650632496).

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

1921800384 is a wasteful number, since it uses less digits than its factorization.

1921800384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22732 (or 22709 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 1921800384 is about 43838.3437643349. The cubic root of 1921800384 is about 1243.2813679395.

The spelling of 1921800384 in words is "one billion, nine hundred twenty-one million, eight hundred thousand, three hundred eighty-four".