2121222102121 has 4 divisors (see below), whose sum is σ = 2245999872852. Its totient is φ = 1996444331392.

The previous prime is 2121222102061. The next prime is 2121222102133. The reversal of 2121222102121 is 1212012221212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 929218881600 + 1192003220521 = 963960^2 + 1091789^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121222102121 - 2²⁹ = 2120685231209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2121222102221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 62388885340 + ... + 62388885373.

It is an arithmetic number, because the mean of its divisors is an integer number (561499968213).

Almost surely, 2^{2121222102121} is an apocalyptic number.

It is an amenable number.

2121222102121 is a deficient number, since it is larger than the sum of its proper divisors (124777770731).

2121222102121 is a wasteful number, since it uses less digits than its factorization.

2121222102121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124777770730.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 2121222102121 its reverse (1212012221212), we get a palindrome (3333234323333).

The spelling of 2121222102121 in words is "two trillion, one hundred twenty-one billion, two hundred twenty-two million, one hundred two thousand, one hundred twenty-one".