17891048849 has 2 divisors, whose sum is σ = 17891048850. Its totient is φ = 17891048848.

The previous prime is 17891048839. The next prime is 17891048947. The reversal of 17891048849 is 94884019871.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15641254225 + 2249794624 = 125065^2 + 47432^2 .

It is an emirp because it is prime and its reverse (94884019871) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-17891048849 is a prime.

It is not a weakly prime, because it can be changed into another prime (17891048839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8945524424 + 8945524425.

It is an arithmetic number, because the mean of its divisors is an integer number (8945524425).

Almost surely, 2^17891048849 is an apocalyptic number.

It is an amenable number.

17891048849 is a deficient number, since it is larger than the sum of its proper divisors (1).

17891048849 is an equidigital number, since it uses as much as digits as its factorization.

17891048849 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4644864, while the sum is 59.

The spelling of 17891048849 in words is "seventeen billion, eight hundred ninety-one million, forty-eight thousand, eight hundred forty-nine".