18859139909 has 4 divisors (see below), whose sum is σ = 19851726240. Its totient is φ = 17866553580.

The previous prime is 18859139879. The next prime is 18859139911. The reversal of 18859139909 is 90993195881.

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.

It is a cyclic number.

It is not a de Polignac number, because 18859139909 - 2¹⁶ = 18859074373 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 (18859139309) 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, 496293137 + ... + 496293174.

It is an arithmetic number, because the mean of its divisors is an integer number (4962931560).

Almost surely, 2^18859139909 is an apocalyptic number.

18859139909 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

18859139909 is a deficient number, since it is larger than the sum of its proper divisors (992586331).

18859139909 is an equidigital number, since it uses as much as digits as its factorization.

18859139909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 992586330.

The product of its (nonzero) digits is 6298560, while the sum is 62.

The spelling of 18859139909 in words is "eighteen billion, eight hundred fifty-nine million, one hundred thirty-nine thousand, nine hundred nine".