213321123121 has 16 divisors (see below), whose sum is σ = 216521294080. Its totient is φ = 210149976960.

The previous prime is 213321123109. The next prime is 213321123151. The reversal of 213321123121 is 121321123312.

It is a cyclic number.

It is not a de Polignac number, because 213321123121 - 2²⁹ = 212784252209 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 213321123092 and 213321123101.

It is not an unprimeable number, because it can be changed into a prime (213321123101) 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, 11639461 + ... + 11657773.

It is an arithmetic number, because the mean of its divisors is an integer number (13532580880).

Almost surely, 2^213321123121 is an apocalyptic number.

It is an amenable number.

213321123121 is a deficient number, since it is larger than the sum of its proper divisors (3200170959).

213321123121 is a wasteful number, since it uses less digits than its factorization.

213321123121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19096.

The product of its digits is 432, while the sum is 22.

Adding to 213321123121 its reverse (121321123312), we get a palindrome (334642246433).

The spelling of 213321123121 in words is "two hundred thirteen billion, three hundred twenty-one million, one hundred twenty-three thousand, one hundred twenty-one".