18440771781139 has 2 divisors, whose sum is σ = 18440771781140. Its totient is φ = 18440771781138.

The previous prime is 18440771781119. The next prime is 18440771781167. The reversal of 18440771781139 is 93118717704481.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18440771781139 - 2⁷ = 18440771781011 is a prime.

It is a super-2 number, since 2×18440771781139² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18440771781119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9220385890569 + 9220385890570.

It is an arithmetic number, because the mean of its divisors is an integer number (9220385890570).

Almost surely, 2^{18440771781139} is an apocalyptic number.

18440771781139 is a deficient number, since it is larger than the sum of its proper divisors (1).

18440771781139 is an equidigital number, since it uses as much as digits as its factorization.

18440771781139 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9483264, while the sum is 61.

It can be divided in two parts, 1844077 and 1781139, that added together give a square (3625216 = 1904²).

The spelling of 18440771781139 in words is "eighteen trillion, four hundred forty billion, seven hundred seventy-one million, seven hundred eighty-one thousand, one hundred thirty-nine".