1221033312 has 48 divisors (see below), whose sum is σ = 3561349680. Its totient is φ = 407010816.

The previous prime is 1221033293. The next prime is 1221033349. The reversal of 1221033312 is 2133301221.

It is a tau number, because it is divible by the number of its divisors (48).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 705753 + ... + 707480.

It is an arithmetic number, because the mean of its divisors is an integer number (74194785).

Almost surely, 2^1221033312 is an apocalyptic number.

1221033312 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1221033312 is an abundant number, since it is smaller than the sum of its proper divisors (2340316368).

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

1221033312 is a wasteful number, since it uses less digits than its factorization.

1221033312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1413252 (or 1413238 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 1221033312 is about 34943.2870806397. The cubic root of 1221033312 is about 1068.8313184047.

Adding to 1221033312 its reverse (2133301221), we get a palindrome (3354334533).

The spelling of 1221033312 in words is "one billion, two hundred twenty-one million, thirty-three thousand, three hundred twelve".