18943638159 has 4 divisors (see below), whose sum is σ = 25258184216. Its totient is φ = 12629092104.

The previous prime is 18943638079. The next prime is 18943638247. The reversal of 18943638159 is 95183634981.

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

It is not a de Polignac number, because 18943638159 - 2¹³ = 18943629967 is a prime.

It is a super-2 number, since 2×18943638159² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18943638099 and 18943638108.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18943638359) 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, 3157273024 + ... + 3157273029.

It is an arithmetic number, because the mean of its divisors is an integer number (6314546054).

Almost surely, 2^18943638159 is an apocalyptic number.

18943638159 is a deficient number, since it is larger than the sum of its proper divisors (6314546057).

18943638159 is an equidigital number, since it uses as much as digits as its factorization.

18943638159 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6314546056.

The product of its digits is 5598720, while the sum is 57.

The spelling of 18943638159 in words is "eighteen billion, nine hundred forty-three million, six hundred thirty-eight thousand, one hundred fifty-nine".