2121121221210 has 128 divisors (see below), whose sum is σ = 5713761254400. Its totient is φ = 559891353600.

The previous prime is 2121121221181. The next prime is 2121121221217. The reversal of 2121121221210 is 121221211212.

2121121221210 is a `hidden beast` number, since 2 + 1 + 211 + 21 + 221 + 210 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (2121121221217) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 151859647 + ... + 151873613.

It is an arithmetic number, because the mean of its divisors is an integer number (44638759800).

Almost surely, 2^{2121121221210} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2121121221210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2856880627200).

2121121221210 is an abundant number, since it is smaller than the sum of its proper divisors (3592640033190).

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

2121121221210 is a wasteful number, since it uses less digits than its factorization.

2121121221210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19653 (or 19647 counting only the distinct ones).

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

Adding to 2121121221210 its reverse (121221211212), we get a palindrome (2242342432422).

The spelling of 2121121221210 in words is "two trillion, one hundred twenty-one billion, one hundred twenty-one million, two hundred twenty-one thousand, two hundred ten".