20031222121 has 2 divisors, whose sum is σ = 20031222122. Its totient is φ = 20031222120.

The previous prime is 20031222073. The next prime is 20031222137. The reversal of 20031222121 is 12122213002.

It is a happy number.

It is an a-pointer prime, because the next prime (20031222137) can be obtained adding 20031222121 to its sum of digits (16).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14643662121 + 5387560000 = 121011^2 + 73400^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20031222121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20031222095 and 20031222104.

It is not a weakly prime, because it can be changed into another prime (20031222161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10015611060 + 10015611061.

It is an arithmetic number, because the mean of its divisors is an integer number (10015611061).

Almost surely, 2^20031222121 is an apocalyptic number.

It is an amenable number.

20031222121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20031222121 is an equidigital number, since it uses as much as digits as its factorization.

20031222121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 20031222121 its reverse (12122213002), we get a palindrome (32153435123).

The spelling of 20031222121 in words is "twenty billion, thirty-one million, two hundred twenty-two thousand, one hundred twenty-one".