231210012221 has 32 divisors (see below), whose sum is σ = 250460356608. Its totient is φ = 212810526720.

The previous prime is 231210012199. The next prime is 231210012263. The reversal of 231210012221 is 122210012132.

It is a cyclic number.

It is not a de Polignac number, because 231210012221 - 2⁶ = 231210012157 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 231210012221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231210012281) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 194784590 + ... + 194785776.

It is an arithmetic number, because the mean of its divisors is an integer number (7826886144).

Almost surely, 2^231210012221 is an apocalyptic number.

It is an amenable number.

231210012221 is a deficient number, since it is larger than the sum of its proper divisors (19250344387).

231210012221 is a wasteful number, since it uses less digits than its factorization.

231210012221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2561.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 231210012221 its reverse (122210012132), we get a palindrome (353420024353).

The spelling of 231210012221 in words is "two hundred thirty-one billion, two hundred ten million, twelve thousand, two hundred twenty-one".