209174506126081 has 2 divisors, whose sum is σ = 209174506126082. Its totient is φ = 209174506126080.

The previous prime is 209174506126073. The next prime is 209174506126109. The reversal of 209174506126081 is 180621605471902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107205730160400 + 101968775965681 = 10354020^2 + 10097959^2 .

It is a cyclic number.

It is not a de Polignac number, because 209174506126081 - 2³ = 209174506126073 is a prime.

It is a super-2 number, since 2×209174506126081² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (209174506126681) 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, 104587253063040 + 104587253063041.

It is an arithmetic number, because the mean of its divisors is an integer number (104587253063041).

Almost surely, 2^{209174506126081} is an apocalyptic number.

It is an amenable number.

209174506126081 is a deficient number, since it is larger than the sum of its proper divisors (1).

209174506126081 is an equidigital number, since it uses as much as digits as its factorization.

209174506126081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1451520, while the sum is 52.

The spelling of 209174506126081 in words is "two hundred nine trillion, one hundred seventy-four billion, five hundred six million, one hundred twenty-six thousand, eighty-one".