2121234221 has 12 divisors (see below), whose sum is σ = 2188603872. Its totient is φ = 2055724728.

The previous prime is 2121234209. The next prime is 2121234229. The reversal of 2121234221 is 1224321212.

It is a de Polignac number, because none of the positive numbers 2^k-2121234221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2121234193 and 2121234202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121234229) 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, 222866 + ... + 232188.

It is an arithmetic number, because the mean of its divisors is an integer number (182383656).

Almost surely, 2^2121234221 is an apocalyptic number.

It is an amenable number.

2121234221 is a deficient number, since it is larger than the sum of its proper divisors (67369651).

2121234221 is an equidigital number, since it uses as much as digits as its factorization.

2121234221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9520 (or 9473 counting only the distinct ones).

The product of its digits is 384, while the sum is 20.

The square root of 2121234221 is about 46056.8585663417. The cubic root of 2121234221 is about 1284.8809048482.

Adding to 2121234221 its reverse (1224321212), we get a palindrome (3345555433).

The spelling of 2121234221 in words is "two billion, one hundred twenty-one million, two hundred thirty-four thousand, two hundred twenty-one".