1221020112 has 40 divisors (see below), whose sum is σ = 3396942304. Its totient is φ = 375698304.

The previous prime is 1221020111. The next prime is 1221020117. The reversal of 1221020112 is 2110201221.

It is a super-2 number, since 2×1221020112² = 2981780227816985088, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221020111) 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, 977758 + ... + 979005.

Almost surely, 2^1221020112 is an apocalyptic number.

1221020112 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1221020112 is an abundant number, since it is smaller than the sum of its proper divisors (2175922192).

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

1221020112 is a wasteful number, since it uses less digits than its factorization.

1221020112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1956787 (or 1956781 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 1221020112 is about 34943.0982026494. The cubic root of 1221020112 is about 1068.8274668515.

Adding to 1221020112 its reverse (2110201221), we get a palindrome (3331221333).

The spelling of 1221020112 in words is "one billion, two hundred twenty-one million, twenty thousand, one hundred twelve".