20010111021209 has 2 divisors, whose sum is σ = 20010111021210. Its totient is φ = 20010111021208.

The previous prime is 20010111021163. The next prime is 20010111021289. The reversal of 20010111021209 is 90212011101002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16665703993225 + 3344407027984 = 4082365^2 + 1828772^2 .

It is a cyclic number.

It is not a de Polignac number, because 20010111021209 - 2²⁸ = 20009842585753 is a prime.

It is a super-2 number, since 2×20010111021209² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20010111021289) 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, 10005055510604 + 10005055510605.

It is an arithmetic number, because the mean of its divisors is an integer number (10005055510605).

Almost surely, 2^{20010111021209} is an apocalyptic number.

It is an amenable number.

20010111021209 is a deficient number, since it is larger than the sum of its proper divisors (1).

20010111021209 is an equidigital number, since it uses as much as digits as its factorization.

20010111021209 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 20010111021209 in words is "twenty trillion, ten billion, one hundred eleven million, twenty-one thousand, two hundred nine".