20011121129 has 2 divisors, whose sum is σ = 20011121130. Its totient is φ = 20011121128.

The previous prime is 20011121113. The next prime is 20011121159. The reversal of 20011121129 is 92112111002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14007195904 + 6003925225 = 118352^2 + 77485^2 .

It is a cyclic number.

It is not a de Polignac number, because 20011121129 - 2⁴ = 20011121113 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20011121129.

It is not a weakly prime, because it can be changed into another prime (20011121159) 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, 10005560564 + 10005560565.

It is an arithmetic number, because the mean of its divisors is an integer number (10005560565).

Almost surely, 2^20011121129 is an apocalyptic number.

It is an amenable number.

20011121129 is a deficient number, since it is larger than the sum of its proper divisors (1).

20011121129 is an equidigital number, since it uses as much as digits as its factorization.

20011121129 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 20.

The spelling of 20011121129 in words is "twenty billion, eleven million, one hundred twenty-one thousand, one hundred twenty-nine".