18320491801 has 4 divisors (see below), whose sum is σ = 18335849652. Its totient is φ = 18305133952.

The previous prime is 18320491789. The next prime is 18320491837. The reversal of 18320491801 is 10819402381.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10819402381 = 20147 ⋅537023.

It can be written as a sum of positive squares in 2 ways, for example, as 3558241801 + 14762250000 = 59651^2 + 121500^2 .

It is a cyclic number.

It is not a de Polignac number, because 18320491801 - 2⁵ = 18320491769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18320491901) 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, 7677136 + ... + 7679521.

It is an arithmetic number, because the mean of its divisors is an integer number (4583962413).

Almost surely, 2^18320491801 is an apocalyptic number.

It is an amenable number.

18320491801 is a deficient number, since it is larger than the sum of its proper divisors (15357851).

18320491801 is a wasteful number, since it uses less digits than its factorization.

18320491801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15357850.

The product of its (nonzero) digits is 13824, while the sum is 37.

The spelling of 18320491801 in words is "eighteen billion, three hundred twenty million, four hundred ninety-one thousand, eight hundred one".