1220203220 has 48 divisors (see below), whose sum is σ = 2740097808. Its totient is φ = 454809600.

The previous prime is 1220203219. The next prime is 1220203223. The reversal of 1220203220 is 223020221.

It can be written as a sum of positive squares in 8 ways, for example, as 9024016 + 1211179204 = 3004^2 + 34802^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1220203195 and 1220203204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220203223) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16574 + ... + 52106.

It is an arithmetic number, because the mean of its divisors is an integer number (57085371).

Almost surely, 2^1220203220 is an apocalyptic number.

1220203220 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 1220203220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1370048904).

1220203220 is an abundant number, since it is smaller than the sum of its proper divisors (1519894588).

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

1220203220 is a wasteful number, since it uses less digits than its factorization.

1220203220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35660 (or 35658 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 1220203220 is about 34931.4073578492. The cubic root of 1220203220 is about 1068.5890565303.

Adding to 1220203220 its reverse (223020221), we get a palindrome (1443223441).

The spelling of 1220203220 in words is "one billion, two hundred twenty million, two hundred three thousand, two hundred twenty".