1822720 has 52 divisors (see below), whose sum is σ = 4423140. Its totient is φ = 720896.

The previous prime is 1822703. The next prime is 1822781. The reversal of 1822720 is 272281.

It can be written as a sum of positive squares in 2 ways, for example, as 495616 + 1327104 = 704^2 + 1152^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1822691 and 1822700.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 20436 + ... + 20524.

2^1822720 is an apocalyptic number.

1822720 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 1822720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2211570).

1822720 is an abundant number, since it is smaller than the sum of its proper divisors (2600420).

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

1822720 is an frugal number, since it uses more digits than its factorization.

1822720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118 (or 96 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 1822720 is about 1350.0814790227. The cubic root of 1822720 is about 122.1537075439.

The spelling of 1822720 in words is "one million, eight hundred twenty-two thousand, seven hundred twenty".