20001113123221 has 2 divisors, whose sum is σ = 20001113123222. Its totient is φ = 20001113123220.

The previous prime is 20001113123161. The next prime is 20001113123231. The reversal of 20001113123221 is 12232131110002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18648241726321 + 1352871396900 = 4318361^2 + 1163130^2 .

It is a cyclic number.

It is not a de Polignac number, because 20001113123221 - 2¹¹ = 20001113121173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20001113123231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000556561610 + 10000556561611.

It is an arithmetic number, because the mean of its divisors is an integer number (10000556561611).

Almost surely, 2^{20001113123221} is an apocalyptic number.

It is an amenable number.

20001113123221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001113123221 is an equidigital number, since it uses as much as digits as its factorization.

20001113123221 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 19.

Adding to 20001113123221 its reverse (12232131110002), we get a palindrome (32233244233223).

The spelling of 20001113123221 in words is "twenty trillion, one billion, one hundred thirteen million, one hundred twenty-three thousand, two hundred twenty-one".