1321233220 has 12 divisors (see below), whose sum is σ = 2774589804. Its totient is φ = 528493280.

The previous prime is 1321233203. The next prime is 1321233247. The reversal of 1321233220 is 223321231.

It can be written as a sum of positive squares in 2 ways, for example, as 380952324 + 940280896 = 19518^2 + 30664^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33030811 + ... + 33030850.

It is an arithmetic number, because the mean of its divisors is an integer number (231215817).

Almost surely, 2^1321233220 is an apocalyptic number.

1321233220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1321233220 is an abundant number, since it is smaller than the sum of its proper divisors (1453356584).

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

1321233220 is a wasteful number, since it uses less digits than its factorization.

1321233220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66061670 (or 66061668 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 19.

The square root of 1321233220 is about 36348.7719187320. The cubic root of 1321233220 is about 1097.3028189612.

Adding to 1321233220 its reverse (223321231), we get a palindrome (1544554451).

The spelling of 1321233220 in words is "one billion, three hundred twenty-one million, two hundred thirty-three thousand, two hundred twenty".