21012111101129 has 2 divisors, whose sum is σ = 21012111101130. Its totient is φ = 21012111101128.

The previous prime is 21012111101039. The next prime is 21012111101141. The reversal of 21012111101129 is 92110111121012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14140645764025 + 6871465337104 = 3760405^2 + 2621348^2 .

It is a cyclic number.

It is not a de Polignac number, because 21012111101129 - 2²⁰ = 21012110052553 is a prime.

It is not a weakly prime, because it can be changed into another prime (21012111101029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10506055550564 + 10506055550565.

It is an arithmetic number, because the mean of its divisors is an integer number (10506055550565).

Almost surely, 2^{21012111101129} is an apocalyptic number.

It is an amenable number.

21012111101129 is a deficient number, since it is larger than the sum of its proper divisors (1).

21012111101129 is an equidigital number, since it uses as much as digits as its factorization.

21012111101129 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 23.

The spelling of 21012111101129 in words is "twenty-one trillion, twelve billion, one hundred eleven million, one hundred one thousand, one hundred twenty-nine".