21201200000129 has 2 divisors, whose sum is σ = 21201200000130. Its totient is φ = 21201200000128.

The previous prime is 21201200000089. The next prime is 21201200000161. The reversal of 21201200000129 is 92100000210212.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10875003366529 + 10326196633600 = 3297727^2 + 3213440^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201200000129 - 2⁸ = 21201199999873 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21201200000129.

It is not a weakly prime, because it can be changed into another prime (21201200005129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600600000064 + 10600600000065.

It is an arithmetic number, because the mean of its divisors is an integer number (10600600000065).

Almost surely, 2^{21201200000129} is an apocalyptic number.

It is an amenable number.

21201200000129 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201200000129 is an equidigital number, since it uses as much as digits as its factorization.

21201200000129 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 20.

The spelling of 21201200000129 in words is "twenty-one trillion, two hundred one billion, two hundred million, one hundred twenty-nine", and thus it is an aban number.