1820320 has 48 divisors (see below), whose sum is σ = 4451328. Its totient is φ = 702720.

The previous prime is 1820311. The next prime is 1820339. The reversal of 1820320 is 230281.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 1820294 and 1820303.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4777 + ... + 5143.

It is an arithmetic number, because the mean of its divisors is an integer number (92736).

2^1820320 is an apocalyptic number.

1820320 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 1820320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2225664).

1820320 is an abundant number, since it is smaller than the sum of its proper divisors (2631008).

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

1820320 is a wasteful number, since it uses less digits than its factorization.

1820320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413 (or 405 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 1820320 is about 1349.1923510011. The cubic root of 1820320 is about 122.1000701841.

The spelling of 1820320 in words is "one million, eight hundred twenty thousand, three hundred twenty".