2031123221 has 2 divisors, whose sum is σ = 2031123222. Its totient is φ = 2031123220.

The previous prime is 2031123179. The next prime is 2031123299. The reversal of 2031123221 is 1223211302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1745986225 + 285136996 = 41785^2 + 16886^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2031123221 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2031123221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2031123121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1015561610 + 1015561611.

It is an arithmetic number, because the mean of its divisors is an integer number (1015561611).

Almost surely, 2^2031123221 is an apocalyptic number.

It is an amenable number.

2031123221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2031123221 is an equidigital number, since it uses as much as digits as its factorization.

2031123221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 2031123221 is about 45067.9844346294. The cubic root of 2031123221 is about 1266.4229060555.

Adding to 2031123221 its reverse (1223211302), we get a palindrome (3254334523).

The spelling of 2031123221 in words is "two billion, thirty-one million, one hundred twenty-three thousand, two hundred twenty-one".