121213112220 has 144 divisors (see below), whose sum is σ = 377998184928. Its totient is φ = 31418150400.

The previous prime is 121213112213. The next prime is 121213112231. The reversal of 121213112220 is 22211312121.

121213112220 is a `hidden beast` number, since 12 + 121 + 311 + 2 + 220 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 121213112193 and 121213112202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6991002 + ... + 7008318.

Almost surely, 2^121213112220 is an apocalyptic number.

121213112220 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 121213112220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (188999092464).

121213112220 is an abundant number, since it is smaller than the sum of its proper divisors (256785072708).

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

121213112220 is a wasteful number, since it uses less digits than its factorization.

121213112220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18420 (or 18415 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 121213112220 its reverse (22211312121), we get a palindrome (143424424341).

The spelling of 121213112220 in words is "one hundred twenty-one billion, two hundred thirteen million, one hundred twelve thousand, two hundred twenty".