1213311220 has 48 divisors (see below), whose sum is σ = 2844249408. Its totient is φ = 430940160.

The previous prime is 1213311217. The next prime is 1213311227. The reversal of 1213311220 is 221133121.

It is a junction number, because it is equal to n+sod(n) for n = 1213311194 and 1213311203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213311227) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 54669 + ... + 73588.

It is an arithmetic number, because the mean of its divisors is an integer number (59255196).

Almost surely, 2^1213311220 is an apocalyptic number.

1213311220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1213311220 is an abundant number, since it is smaller than the sum of its proper divisors (1630938188).

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

1213311220 is a wasteful number, since it uses less digits than its factorization.

1213311220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128320 (or 128318 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1213311220 is about 34832.6171856207. The cubic root of 1213311220 is about 1066.5733744362.

Adding to 1213311220 its reverse (221133121), we get a palindrome (1434444341).

The spelling of 1213311220 in words is "one billion, two hundred thirteen million, three hundred eleven thousand, two hundred twenty".