21221202002129 has 2 divisors, whose sum is σ = 21221202002130. Its totient is φ = 21221202002128.

The previous prime is 21221202002111. The next prime is 21221202002197. The reversal of 21221202002129 is 92120020212212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20611009804225 + 610192197904 = 4539935^2 + 781148^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21221202002129 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21221202002098 and 21221202002107.

It is not a weakly prime, because it can be changed into another prime (21221202002929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610601001064 + 10610601001065.

It is an arithmetic number, because the mean of its divisors is an integer number (10610601001065).

Almost surely, 2^{21221202002129} is an apocalyptic number.

It is an amenable number.

21221202002129 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221202002129 is an equidigital number, since it uses as much as digits as its factorization.

21221202002129 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 26.

The spelling of 21221202002129 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred two million, two thousand, one hundred twenty-nine".