1220121312 has 48 divisors (see below), whose sum is σ = 3306143232. Its totient is φ = 393586560.

The previous prime is 1220121283. The next prime is 1220121313. The reversal of 1220121312 is 2131210221.

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

It is a junction number, because it is equal to n+sod(n) for n = 1220121291 and 1220121300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220121313) 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 7 ways as a sum of consecutive naturals, for example, 202018 + ... + 207969.

It is an arithmetic number, because the mean of its divisors is an integer number (68877984).

Almost surely, 2^1220121312 is an apocalyptic number.

1220121312 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1220121312 is an abundant number, since it is smaller than the sum of its proper divisors (2086021920).

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

1220121312 is a wasteful number, since it uses less digits than its factorization.

1220121312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410031 (or 410023 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 1220121312 is about 34930.2349262068. The cubic root of 1220121312 is about 1068.5651457725.

Adding to 1220121312 its reverse (2131210221), we get a palindrome (3351331533).

The spelling of 1220121312 in words is "one billion, two hundred twenty million, one hundred twenty-one thousand, three hundred twelve".