1921280 has 72 divisors (see below), whose sum is σ = 4905600. Its totient is φ = 718848.

The previous prime is 1921277. The next prime is 1921307. The reversal of 1921280 is 821291.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24281 + ... + 24359.

2^1921280 is an apocalyptic number.

1921280 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 1921280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2452800).

1921280 is an abundant number, since it is smaller than the sum of its proper divisors (2984320).

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

1921280 is an equidigital number, since it uses as much as digits as its factorization.

1921280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119 (or 105 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 1921280 is about 1386.1024493161. The cubic root of 1921280 is about 124.3169139472.

The spelling of 1921280 in words is "one million, nine hundred twenty-one thousand, two hundred eighty".