1211233220 has 12 divisors (see below), whose sum is σ = 2543589804. Its totient is φ = 484493280.

The previous prime is 1211233217. The next prime is 1211233229. The reversal of 1211233220 is 223321121.

It can be written as a sum of positive squares in 2 ways, for example, as 465178624 + 746054596 = 21568^2 + 27314^2 .

It is not an unprimeable number, because it can be changed into a prime (1211233229) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30280811 + ... + 30280850.

It is an arithmetic number, because the mean of its divisors is an integer number (211965817).

Almost surely, 2^1211233220 is an apocalyptic number.

1211233220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211233220 is an abundant number, since it is smaller than the sum of its proper divisors (1332356584).

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

1211233220 is a wasteful number, since it uses less digits than its factorization.

1211233220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60561670 (or 60561668 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 1211233220 is about 34802.7760387013. The cubic root of 1211233220 is about 1065.9641309254.

Adding to 1211233220 its reverse (223321121), we get a palindrome (1434554341).

The spelling of 1211233220 in words is "one billion, two hundred eleven million, two hundred thirty-three thousand, two hundred twenty".