1243351220 has 48 divisors (see below), whose sum is σ = 2705346000. Its totient is φ = 480002432.

The previous prime is 1243351201. The next prime is 1243351223. The reversal of 1243351220 is 221533421.

It can be written as a sum of positive squares in 8 ways, for example, as 37039396 + 1206311824 = 6086^2 + 34732^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243351223) 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, 486506 + ... + 489054.

It is an arithmetic number, because the mean of its divisors is an integer number (56361375).

Almost surely, 2^1243351220 is an apocalyptic number.

1243351220 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 1243351220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1352673000).

1243351220 is an abundant number, since it is smaller than the sum of its proper divisors (1461994780).

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

1243351220 is an equidigital number, since it uses as much as digits as its factorization.

1243351220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2645 (or 2585 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 1243351220 is about 35261.1857429667. The cubic root of 1243351220 is about 1075.3040337088.

Adding to 1243351220 its reverse (221533421), we get a palindrome (1464884641).

The spelling of 1243351220 in words is "one billion, two hundred forty-three million, three hundred fifty-one thousand, two hundred twenty".