1221323112 has 48 divisors (see below), whose sum is σ = 3502327140. Its totient is φ = 383159808.

The previous prime is 1221323063. The next prime is 1221323119. The reversal of 1221323112 is 2113231221.

It can be written as a sum of positive squares in 2 ways, for example, as 1072824516 + 148498596 = 32754^2 + 12186^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (1221323119) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 497683 + ... + 500130.

Almost surely, 2^1221323112 is an apocalyptic number.

1221323112 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1221323112 is an abundant number, since it is smaller than the sum of its proper divisors (2281004028).

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

1221323112 is a wasteful number, since it uses less digits than its factorization.

1221323112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 997842 (or 997835 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 1221323112 is about 34947.4335538391. The cubic root of 1221323112 is about 1068.9158705107.

Adding to 1221323112 its reverse (2113231221), we get a palindrome (3334554333).

The spelling of 1221323112 in words is "one billion, two hundred twenty-one million, three hundred twenty-three thousand, one hundred twelve".