17981144563 has 2 divisors, whose sum is σ = 17981144564. Its totient is φ = 17981144562.

The previous prime is 17981144509. The next prime is 17981144581. The reversal of 17981144563 is 36544118971.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-17981144563 is a prime.

It is not a weakly prime, because it can be changed into another prime (17981144663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8990572281 + 8990572282.

It is an arithmetic number, because the mean of its divisors is an integer number (8990572282).

Almost surely, 2^17981144563 is an apocalyptic number.

17981144563 is a deficient number, since it is larger than the sum of its proper divisors (1).

17981144563 is an equidigital number, since it uses as much as digits as its factorization.

17981144563 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 725760, while the sum is 49.

The spelling of 17981144563 in words is "seventeen billion, nine hundred eighty-one million, one hundred forty-four thousand, five hundred sixty-three".