231212233202221 has 4 divisors (see below), whose sum is σ = 231228569839932. Its totient is φ = 231195896564512.

The previous prime is 231212233202191. The next prime is 231212233202299. The reversal of 231212233202221 is 122202332212132.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 48314468641321 + 182897764560900 = 6950861^2 + 13523970^2 .

It is a cyclic number.

It is not a de Polignac number, because 231212233202221 - 2¹³ = 231212233194029 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 231212233202221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231212233203221) 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, 8168297626 + ... + 8168325931.

It is an arithmetic number, because the mean of its divisors is an integer number (57807142459983).

Almost surely, 2^{231212233202221} is an apocalyptic number.

It is an amenable number.

231212233202221 is a deficient number, since it is larger than the sum of its proper divisors (16336637711).

231212233202221 is a wasteful number, since it uses less digits than its factorization.

231212233202221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16336637710.

The product of its (nonzero) digits is 6912, while the sum is 28.

Adding to 231212233202221 its reverse (122202332212132), we get a palindrome (353414565414353).

The spelling of 231212233202221 in words is "two hundred thirty-one trillion, two hundred twelve billion, two hundred thirty-three million, two hundred two thousand, two hundred twenty-one".