2121312133221 has 32 divisors (see below), whose sum is σ = 2981411452800. Its totient is φ = 1339793495040.

The previous prime is 2121312133159. The next prime is 2121312133231. The reversal of 2121312133221 is 1223312131212.

It is not a de Polignac number, because 2121312133221 - 2¹¹ = 2121312131173 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2121312133191 and 2121312133200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121312133231) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31336 + ... + 2060001.

It is an arithmetic number, because the mean of its divisors is an integer number (93169107900).

Almost surely, 2^{2121312133221} is an apocalyptic number.

It is an amenable number.

2121312133221 is a deficient number, since it is larger than the sum of its proper divisors (860099319579).

2121312133221 is a wasteful number, since it uses less digits than its factorization.

2121312133221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2091589.

The product of its digits is 864, while the sum is 24.

Adding to 2121312133221 its reverse (1223312131212), we get a palindrome (3344624264433).

The spelling of 2121312133221 in words is "two trillion, one hundred twenty-one billion, three hundred twelve million, one hundred thirty-three thousand, two hundred twenty-one".