26990891173 has 2 divisors, whose sum is σ = 26990891174. Its totient is φ = 26990891172.

The previous prime is 26990891171. The next prime is 26990891233. The reversal of 26990891173 is 37119809962.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15198451524 + 11792439649 = 123282^2 + 108593^2 .

It is a cyclic number.

It is not a de Polignac number, because 26990891173 - 2¹ = 26990891171 is a prime.

Together with 26990891171, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26990891171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13495445586 + 13495445587.

It is an arithmetic number, because the mean of its divisors is an integer number (13495445587).

Almost surely, 2^26990891173 is an apocalyptic number.

It is an amenable number.

26990891173 is a deficient number, since it is larger than the sum of its proper divisors (1).

26990891173 is an equidigital number, since it uses as much as digits as its factorization.

26990891173 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1469664, while the sum is 55.

The spelling of 26990891173 in words is "twenty-six billion, nine hundred ninety million, eight hundred ninety-one thousand, one hundred seventy-three".