1720224 has 96 divisors (see below), whose sum is σ = 5503680. Its totient is φ = 518400.

The previous prime is 1720223. The next prime is 1720231. The reversal of 1720224 is 4220271.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×1720224² = 5918341220352, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 1720197 and 1720206.

It is not an unprimeable number, because it can be changed into a prime (1720223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9414 + ... + 9594.

It is an arithmetic number, because the mean of its divisors is an integer number (57330).

2^1720224 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1720224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2751840).

1720224 is an abundant number, since it is smaller than the sum of its proper divisors (3783456).

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

1720224 is a wasteful number, since it uses less digits than its factorization.

1720224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211 (or 197 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 18.

The square root of 1720224 is about 1311.5731012795. The cubic root of 1720224 is about 119.8197293230.

Adding to 1720224 its reverse (4220271), we get a palindrome (5940495).

The spelling of 1720224 in words is "one million, seven hundred twenty thousand, two hundred twenty-four".