18311423477 has 4 divisors (see below), whose sum is σ = 18330166956. Its totient is φ = 18292680000.

The previous prime is 18311423467. The next prime is 18311423479. The reversal of 18311423477 is 77432411381.

It is a happy number.

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 10175563876 + 8135859601 = 100874^2 + 90199^2 .

It is a cyclic number.

It is not a de Polignac number, because 18311423477 - 2⁴ = 18311423461 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 (18311423479) 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 3 ways as a sum of consecutive naturals, for example, 9370274 + ... + 9372227.

It is an arithmetic number, because the mean of its divisors is an integer number (4582541739).

Almost surely, 2^18311423477 is an apocalyptic number.

It is an amenable number.

18311423477 is a deficient number, since it is larger than the sum of its proper divisors (18743479).

18311423477 is an equidigital number, since it uses as much as digits as its factorization.

18311423477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18743478.

The product of its digits is 112896, while the sum is 41.

The spelling of 18311423477 in words is "eighteen billion, three hundred eleven million, four hundred twenty-three thousand, four hundred seventy-seven".