18181911001 has 4 divisors (see below), whose sum is σ = 18182867472. Its totient is φ = 18180954532.

The previous prime is 18181910993. The next prime is 18181911031. The reversal of 18181911001 is 10011918181.

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: 10011918181 = 523 ⋅19143247.

It is a cyclic number.

It is not a de Polignac number, because 18181911001 - 2³ = 18181910993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18181911031) 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, 449131 + ... + 487936.

It is an arithmetic number, because the mean of its divisors is an integer number (4545716868).

Almost surely, 2^18181911001 is an apocalyptic number.

It is an amenable number.

18181911001 is a deficient number, since it is larger than the sum of its proper divisors (956471).

18181911001 is an equidigital number, since it uses as much as digits as its factorization.

18181911001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 956470.

The product of its (nonzero) digits is 576, while the sum is 31.

The spelling of 18181911001 in words is "eighteen billion, one hundred eighty-one million, nine hundred eleven thousand, one".