1212121102221 has 12 divisors (see below), whose sum is σ = 1751872127200. Its totient is φ = 807605103240.

The previous prime is 1212121102187. The next prime is 1212121102259. The reversal of 1212121102221 is 1222011212121.

1212121102221 is a `hidden beast` number, since 121 + 212 + 110 + 2 + 221 = 666.

It is not a de Polignac number, because 1212121102221 - 2¹⁰ = 1212121101197 is a prime.

It is a super-2 number, since 2×1212121102221² (a number of 25 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 = 1212121102194 and 1212121102203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212121104221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 39619825 + ... + 39650406.

Almost surely, 2^{1212121102221} is an apocalyptic number.

It is an amenable number.

1212121102221 is a deficient number, since it is larger than the sum of its proper divisors (539751024979).

1212121102221 is a wasteful number, since it uses less digits than its factorization.

1212121102221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79271936 (or 79271933 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 1212121102221 its reverse (1222011212121), we get a palindrome (2434132314342).

The spelling of 1212121102221 in words is "one trillion, two hundred twelve billion, one hundred twenty-one million, one hundred two thousand, two hundred twenty-one".