213103031221 has 4 divisors (see below), whose sum is σ = 218058915712. Its totient is φ = 208147146732.

The previous prime is 213103031203. The next prime is 213103031227. The reversal of 213103031221 is 122130301312.

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 213103031221 - 2²⁷ = 212968813493 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 (213103031227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2477942181 + ... + 2477942266.

It is an arithmetic number, because the mean of its divisors is an integer number (54514728928).

Almost surely, 2^213103031221 is an apocalyptic number.

It is an amenable number.

213103031221 is a deficient number, since it is larger than the sum of its proper divisors (4955884491).

213103031221 is an equidigital number, since it uses as much as digits as its factorization.

213103031221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4955884490.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 213103031221 its reverse (122130301312), we get a palindrome (335233332533).

The spelling of 213103031221 in words is "two hundred thirteen billion, one hundred three million, thirty-one thousand, two hundred twenty-one".