1221111121120 has 96 divisors (see below), whose sum is σ = 3178296618336. Its totient is φ = 439643904000.

The previous prime is 1221111121093. The next prime is 1221111121127. The reversal of 1221111121120 is 211211111221.

It is a super-2 number, since 2×1221111121120² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 1221111121094 and 1221111121103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221111121127) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3256959 + ... + 3612478.

It is an arithmetic number, because the mean of its divisors is an integer number (33107256441).

Almost surely, 2^{1221111121120} is an apocalyptic number.

1221111121120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221111121120 is an abundant number, since it is smaller than the sum of its proper divisors (1957185497216).

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

1221111121120 is a wasteful number, since it uses less digits than its factorization.

1221111121120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6869564 (or 6869556 counting only the distinct ones).

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

Adding to 1221111121120 its reverse (211211111221), we get a palindrome (1432322232341).

The spelling of 1221111121120 in words is "one trillion, two hundred twenty-one billion, one hundred eleven million, one hundred twenty-one thousand, one hundred twenty".