231221030213 has 4 divisors (see below), whose sum is σ = 233465894688. Its totient is φ = 228976165740.

The previous prime is 231221030113. The next prime is 231221030237. The reversal of 231221030213 is 312030122132.

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 231221030213 - 2¹⁸ = 231220768069 is a prime.

It is a super-2 number, since 2×231221030213² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231221030113) 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, 1122432083 + ... + 1122432288.

It is an arithmetic number, because the mean of its divisors is an integer number (58366473672).

Almost surely, 2^231221030213 is an apocalyptic number.

It is an amenable number.

231221030213 is a deficient number, since it is larger than the sum of its proper divisors (2244864475).

231221030213 is a wasteful number, since it uses less digits than its factorization.

231221030213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2244864474.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 231221030213 its reverse (312030122132), we get a palindrome (543251152345).

The spelling of 231221030213 in words is "two hundred thirty-one billion, two hundred twenty-one million, thirty thousand, two hundred thirteen".