21212233130221 has 4 divisors (see below), whose sum is σ = 24242552148832. Its totient is φ = 18181914111612.

The previous prime is 21212233130213. The next prime is 21212233130233. The reversal of 21212233130221 is 12203133221212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21212233130221 - 2³ = 21212233130213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212233160221) 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, 1515159509295 + ... + 1515159509308.

It is an arithmetic number, because the mean of its divisors is an integer number (6060638037208).

Almost surely, 2^{21212233130221} is an apocalyptic number.

It is an amenable number.

21212233130221 is a deficient number, since it is larger than the sum of its proper divisors (3030319018611).

21212233130221 is an equidigital number, since it uses as much as digits as its factorization.

21212233130221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3030319018610.

The product of its (nonzero) digits is 1728, while the sum is 25.

Adding to 21212233130221 its reverse (12203133221212), we get a palindrome (33415366351433).

Subtracting from 21212233130221 its reverse (12203133221212), we obtain a palindrome (9009099909009).

The spelling of 21212233130221 in words is "twenty-one trillion, two hundred twelve billion, two hundred thirty-three million, one hundred thirty thousand, two hundred twenty-one".