18840781077 has 16 divisors (see below), whose sum is σ = 25278948288. Its totient is φ = 12481640960.

The previous prime is 18840781067. The next prime is 18840781079. The reversal of 18840781077 is 77018704881.

It is a cyclic number.

It is not a de Polignac number, because 18840781077 - 2⁸ = 18840780821 is a prime.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18840781079) 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 in 15 ways as a sum of consecutive naturals, for example, 1171702 + ... + 1187672.

It is an arithmetic number, because the mean of its divisors is an integer number (1579934268).

Almost surely, 2^18840781077 is an apocalyptic number.

It is an amenable number.

18840781077 is a deficient number, since it is larger than the sum of its proper divisors (6438167211).

18840781077 is a wasteful number, since it uses less digits than its factorization.

18840781077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18420.

The product of its (nonzero) digits is 702464, while the sum is 51.

The spelling of 18840781077 in words is "eighteen billion, eight hundred forty million, seven hundred eighty-one thousand, seventy-seven".