221121122121 has 12 divisors (see below), whose sum is σ = 319402482672. Its totient is φ = 147411632376.

The previous prime is 221121122099. The next prime is 221121122129. The reversal of 221121122121 is 121221121122.

221121122121 is a `hidden beast` number, since 2 + 211 + 211 + 221 + 21 = 666.

It is not a de Polignac number, because 221121122121 - 2³¹ = 218973638473 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221121122094 and 221121122103.

It is not an unprimeable number, because it can be changed into a prime (221121122129) 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, 493090 + ... + 827876.

It is an arithmetic number, because the mean of its divisors is an integer number (26616873556).

Almost surely, 2^221121122121 is an apocalyptic number.

It is an amenable number.

221121122121 is a deficient number, since it is larger than the sum of its proper divisors (98281360551).

221121122121 is a wasteful number, since it uses less digits than its factorization.

221121122121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408180 (or 408177 counting only the distinct ones).

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

Adding to 221121122121 its reverse (121221121122), we get a palindrome (342342243243).

Subtracting from 221121122121 its reverse (121221121122), we obtain a palindrome (99900000999).

It can be divided in two parts, 221121122 and 121, that multiplied together give a palindrome (26755655762).

The spelling of 221121122121 in words is "two hundred twenty-one billion, one hundred twenty-one million, one hundred twenty-two thousand, one hundred twenty-one".