20131233212221 has 4 divisors (see below), whose sum is σ = 21006504221472. Its totient is φ = 19255962202972.

The previous prime is 20131233212119. The next prime is 20131233212227. The reversal of 20131233212221 is 12221233213102.

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 20131233212221 - 2⁹ = 20131233211709 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 (20131233212227) 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, 437635504591 + ... + 437635504636.

It is an arithmetic number, because the mean of its divisors is an integer number (5251626055368).

Almost surely, 2^{20131233212221} is an apocalyptic number.

It is an amenable number.

20131233212221 is a deficient number, since it is larger than the sum of its proper divisors (875271009251).

20131233212221 is an equidigital number, since it uses as much as digits as its factorization.

20131233212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 875271009250.

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

Adding to 20131233212221 its reverse (12221233213102), we get a palindrome (32352466425323).

The spelling of 20131233212221 in words is "twenty trillion, one hundred thirty-one billion, two hundred thirty-three million, two hundred twelve thousand, two hundred twenty-one".