1220320 has 48 divisors (see below), whose sum is σ = 2993760. Its totient is φ = 469504.

The previous prime is 1220309. The next prime is 1220327. The reversal of 1220320 is 230221.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 1220297 and 1220306.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220327) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4509 + ... + 4771.

It is an arithmetic number, because the mean of its divisors is an integer number (62370).

2^1220320 is an apocalyptic number.

1220320 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 1220320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1496880).

1220320 is an abundant number, since it is smaller than the sum of its proper divisors (1773440).

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

1220320 is a wasteful number, since it uses less digits than its factorization.

1220320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307 (or 299 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 1220320 is about 1104.6809494148. The cubic root of 1220320 is about 106.8623145346.

Adding to 1220320 its reverse (230221), we get a palindrome (1450541).

Subtracting from 1220320 its reverse (230221), we obtain a palindrome (990099).

It can be divided in two parts, 1220 and 320, that added together give a triangular number (1540 = T₅₅).

The spelling of 1220320 in words is "one million, two hundred twenty thousand, three hundred twenty".