21001002220129 has 2 divisors, whose sum is σ = 21001002220130. Its totient is φ = 21001002220128.

The previous prime is 21001002220123. The next prime is 21001002220147. The reversal of 21001002220129 is 92102220010012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20600342337600 + 400659882529 = 4538760^2 + 632977^2 .

It is a cyclic number.

It is not a de Polignac number, because 21001002220129 - 2¹⁹ = 21001001695841 is a prime.

It is not a weakly prime, because it can be changed into another prime (21001002220123) 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, 10500501110064 + 10500501110065.

It is an arithmetic number, because the mean of its divisors is an integer number (10500501110065).

Almost surely, 2^{21001002220129} is an apocalyptic number.

It is an amenable number.

21001002220129 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001002220129 is an equidigital number, since it uses as much as digits as its factorization.

21001002220129 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 22.

The spelling of 21001002220129 in words is "twenty-one trillion, one billion, two million, two hundred twenty thousand, one hundred twenty-nine".