18131611477747 has 4 divisors (see below), whose sum is σ = 18180221696560. Its totient is φ = 18083001258936.

The previous prime is 18131611477723. The next prime is 18131611477757. The reversal of 18131611477747 is 74777411613181.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18131611477747 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18131611477691 and 18131611477700.

It is not an unprimeable number, because it can be changed into a prime (18131611477757) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24305108847 + ... + 24305109592.

It is an arithmetic number, because the mean of its divisors is an integer number (4545055424140).

Almost surely, 2^{18131611477747} is an apocalyptic number.

18131611477747 is a deficient number, since it is larger than the sum of its proper divisors (48610218813).

18131611477747 is an equidigital number, since it uses as much as digits as its factorization.

18131611477747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48610218812.

The product of its digits is 5531904, while the sum is 58.

The spelling of 18131611477747 in words is "eighteen trillion, one hundred thirty-one billion, six hundred eleven million, four hundred seventy-seven thousand, seven hundred forty-seven".