21131221033213 has 8 divisors (see below), whose sum is σ = 21416288100480. Its totient is φ = 20846593547520.

The previous prime is 21131221033199. The next prime is 21131221033217. The reversal of 21131221033213 is 31233012213112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21131221033213 - 2³⁷ = 20993782079741 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 (21131221033217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 109798603 + ... + 109990888.

It is an arithmetic number, because the mean of its divisors is an integer number (2677036012560).

Almost surely, 2^{21131221033213} is an apocalyptic number.

It is an amenable number.

21131221033213 is a deficient number, since it is larger than the sum of its proper divisors (285067067267).

21131221033213 is a wasteful number, since it uses less digits than its factorization.

21131221033213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219790787.

The product of its (nonzero) digits is 1296, while the sum is 25.

Adding to 21131221033213 its reverse (31233012213112), we get a palindrome (52364233246325).

The spelling of 21131221033213 in words is "twenty-one trillion, one hundred thirty-one billion, two hundred twenty-one million, thirty-three thousand, two hundred thirteen".