20001112101221 has 2 divisors, whose sum is σ = 20001112101222. Its totient is φ = 20001112101220.

The previous prime is 20001112101197. The next prime is 20001112101323. The reversal of 20001112101221 is 12210121110002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18870900724225 + 1130211376996 = 4344065^2 + 1063114^2 .

It is a cyclic number.

It is not a de Polignac number, because 20001112101221 - 2²² = 20001107906917 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20001112101196 and 20001112101205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20001112104221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000556050610 + 10000556050611.

It is an arithmetic number, because the mean of its divisors is an integer number (10000556050611).

Almost surely, 2^{20001112101221} is an apocalyptic number.

It is an amenable number.

20001112101221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001112101221 is an equidigital number, since it uses as much as digits as its factorization.

20001112101221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 20001112101221 its reverse (12210121110002), we get a palindrome (32211233211223).

The spelling of 20001112101221 in words is "twenty trillion, one billion, one hundred twelve million, one hundred one thousand, two hundred twenty-one".