1212221100120 has 128 divisors (see below), whose sum is σ = 3673275091200. Its totient is φ = 320008905216.

The previous prime is 1212221100049. The next prime is 1212221100121. The reversal of 1212221100120 is 210011222121.

It is a super-2 number, since 2×1212221100120² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 1212221100120.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212221100121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 18315327 + ... + 18381393.

It is an arithmetic number, because the mean of its divisors is an integer number (28697461650).

Almost surely, 2^{1212221100120} is an apocalyptic number.

1212221100120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1212221100120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1836637545600).

1212221100120 is an abundant number, since it is smaller than the sum of its proper divisors (2461053991080).

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

1212221100120 is a wasteful number, since it uses less digits than its factorization.

1212221100120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67617 (or 67613 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 1212221100120 its reverse (210011222121), we get a palindrome (1422232322241).

The spelling of 1212221100120 in words is "one trillion, two hundred twelve billion, two hundred twenty-one million, one hundred thousand, one hundred twenty".