20001100121 has 2 divisors, whose sum is σ = 20001100122. Its totient is φ = 20001100120.

The previous prime is 20001100111. The next prime is 20001100169. The reversal of 20001100121 is 12100110002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19365505600 + 635594521 = 139160^2 + 25211^2 .

It is a cyclic number.

It is not a de Polignac number, because 20001100121 - 2⁶ = 20001100057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20001100099 and 20001100108.

It is not a weakly prime, because it can be changed into another prime (20001100111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000550060 + 10000550061.

It is an arithmetic number, because the mean of its divisors is an integer number (10000550061).

Almost surely, 2^20001100121 is an apocalyptic number.

It is an amenable number.

20001100121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001100121 is an equidigital number, since it uses as much as digits as its factorization.

20001100121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 20001100121 its reverse (12100110002), we get a palindrome (32101210123).

The spelling of 20001100121 in words is "twenty billion, one million, one hundred thousand, one hundred twenty-one".