18440771781167 has 2 divisors, whose sum is σ = 18440771781168. Its totient is φ = 18440771781166.

The previous prime is 18440771781139. The next prime is 18440771781209. The reversal of 18440771781167 is 76118717704481.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18440771781167 - 2⁴⁰ = 17341260153391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18440771784167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9220385890583 + 9220385890584.

It is an arithmetic number, because the mean of its divisors is an integer number (9220385890584).

Almost surely, 2^{18440771781167} is an apocalyptic number.

18440771781167 is a deficient number, since it is larger than the sum of its proper divisors (1).

18440771781167 is an equidigital number, since it uses as much as digits as its factorization.

18440771781167 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14751744, while the sum is 62.

The spelling of 18440771781167 in words is "eighteen trillion, four hundred forty billion, seven hundred seventy-one million, seven hundred eighty-one thousand, one hundred sixty-seven".