121201212111221 has 16 divisors (see below), whose sum is σ = 132612536966400. Its totient is φ = 109855541114880.

The previous prime is 121201212111191. The next prime is 121201212111223. The reversal of 121201212111221 is 122111212102121.

It is a happy number.

It is not a de Polignac number, because 121201212111221 - 2⁶ = 121201212111157 is a prime.

It is a super-2 number, since 2×121201212111221² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121201212111193 and 121201212111202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121201212111223) 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, 12638405 + ... + 20053221.

It is an arithmetic number, because the mean of its divisors is an integer number (8288283560400).

Almost surely, 2^{121201212111221} is an apocalyptic number.

121201212111221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

121201212111221 is a deficient number, since it is larger than the sum of its proper divisors (11411324855179).

121201212111221 is a wasteful number, since it uses less digits than its factorization.

121201212111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7419244.

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 121201212111221 its reverse (122111212102121), we get a palindrome (243312424213342).

The spelling of 121201212111221 in words is "one hundred twenty-one trillion, two hundred one billion, two hundred twelve million, one hundred eleven thousand, two hundred twenty-one".