2011972118509 has 2 divisors, whose sum is σ = 2011972118510. Its totient is φ = 2011972118508.

The previous prime is 2011972118503. The next prime is 2011972118549. The reversal of 2011972118509 is 9058112791102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1886081982409 + 125890136100 = 1373347^2 + 354810^2 .

It is a cyclic number.

It is not a de Polignac number, because 2011972118509 - 2⁷ = 2011972118381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2011972118503) 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, 1005986059254 + 1005986059255.

It is an arithmetic number, because the mean of its divisors is an integer number (1005986059255).

Almost surely, 2^{2011972118509} is an apocalyptic number.

It is an amenable number.

2011972118509 is a deficient number, since it is larger than the sum of its proper divisors (1).

2011972118509 is an equidigital number, since it uses as much as digits as its factorization.

2011972118509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90720, while the sum is 46.

The spelling of 2011972118509 in words is "two trillion, eleven billion, nine hundred seventy-two million, one hundred eighteen thousand, five hundred nine".