18438971117077 has 16 divisors (see below), whose sum is σ = 21534061086720. Its totient is φ = 15462816428592.

The previous prime is 18438971117057. The next prime is 18438971117089. The reversal of 18438971117077 is 77071117983481.

It is a cyclic number.

It is not a de Polignac number, because 18438971117077 - 2¹¹ = 18438971115029 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18438971117027) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 154001377 + ... + 154121062.

It is an arithmetic number, because the mean of its divisors is an integer number (1345878817920).

Almost surely, 2^{18438971117077} is an apocalyptic number.

It is an amenable number.

18438971117077 is a deficient number, since it is larger than the sum of its proper divisors (3095089969643).

18438971117077 is a wasteful number, since it uses less digits than its factorization.

18438971117077 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308122632.

The product of its (nonzero) digits is 16595712, while the sum is 64.

The spelling of 18438971117077 in words is "eighteen trillion, four hundred thirty-eight billion, nine hundred seventy-one million, one hundred seventeen thousand, seventy-seven".