18817791673 has 4 divisors (see below), whose sum is σ = 18870209280. Its totient is φ = 18765374068.

The previous prime is 18817791661. The next prime is 18817791677. The reversal of 18817791673 is 37619771881.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 37619771881 = 23279 ⋅1616039.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18817791673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18817791677) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26208265 + ... + 26208982.

It is an arithmetic number, because the mean of its divisors is an integer number (4717552320).

Almost surely, 2^18817791673 is an apocalyptic number.

It is an amenable number.

18817791673 is a deficient number, since it is larger than the sum of its proper divisors (52417607).

18817791673 is an equidigital number, since it uses as much as digits as its factorization.

18817791673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52417606.

The product of its digits is 3556224, while the sum is 58.

The spelling of 18817791673 in words is "eighteen billion, eight hundred seventeen million, seven hundred ninety-one thousand, six hundred seventy-three".