18731355077 has 4 divisors (see below), whose sum is σ = 18744920076. Its totient is φ = 18717790080.

The previous prime is 18731355073. The next prime is 18731355103. The reversal of 18731355077 is 77055313781.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13044837796 + 5686517281 = 114214^2 + 75409^2 .

It is a cyclic number.

It is not a de Polignac number, because 18731355077 - 2² = 18731355073 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18731355073) 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 in 3 ways as a sum of consecutive naturals, for example, 6780428 + ... + 6783189.

It is an arithmetic number, because the mean of its divisors is an integer number (4686230019).

Almost surely, 2^18731355077 is an apocalyptic number.

It is an amenable number.

18731355077 is a deficient number, since it is larger than the sum of its proper divisors (13564999).

18731355077 is a wasteful number, since it uses less digits than its factorization.

18731355077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13564998.

The product of its (nonzero) digits is 617400, while the sum is 47.

The spelling of 18731355077 in words is "eighteen billion, seven hundred thirty-one million, three hundred fifty-five thousand, seventy-seven".