21120211001009 has 2 divisors, whose sum is σ = 21120211001010. Its totient is φ = 21120211001008.

The previous prime is 21120211001003. The next prime is 21120211001047. The reversal of 21120211001009 is 90010011202112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18995476224400 + 2124734776609 = 4358380^2 + 1457647^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21120211001009 is a prime.

It is a super-4 number, since 4×21120211001009⁴ (a number of 54 digits) contains 4444 as substring.

It is not a weakly prime, because it can be changed into another prime (21120211001003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560105500504 + 10560105500505.

It is an arithmetic number, because the mean of its divisors is an integer number (10560105500505).

Almost surely, 2^{21120211001009} is an apocalyptic number.

It is an amenable number.

21120211001009 is a deficient number, since it is larger than the sum of its proper divisors (1).

21120211001009 is an equidigital number, since it uses as much as digits as its factorization.

21120211001009 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 21120211001009 in words is "twenty-one trillion, one hundred twenty billion, two hundred eleven million, one thousand, nine".