18823016809 has 3 divisors (see below), whose sum is σ = 18823154007. Its totient is φ = 18822879612.

The previous prime is 18823016801. The next prime is 18823016831. The reversal of 18823016809 is 90861032881.

The square root of 18823016809 is 137197.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 90861032881 = 113 ⋅804079937.

It can be written as a sum of positive squares in only one way, i.e., 12867499225 + 5955517584 = 113435^2 + 77172^2 .

It is not a de Polignac number, because 18823016809 - 2³ = 18823016801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18823016801) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 68599 + ... + 205795.

It is an arithmetic number, because the mean of its divisors is an integer number (6274384669).

Almost surely, 2^18823016809 is an apocalyptic number.

18823016809 is the 137197-th square number.

18823016809 is the 68599-th centered octagonal number.

It is an amenable number.

18823016809 is a deficient number, since it is larger than the sum of its proper divisors (137198).

18823016809 is an frugal number, since it uses more digits than its factorization.

18823016809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274394 (or 137197 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 46.

The spelling of 18823016809 in words is "eighteen billion, eight hundred twenty-three million, sixteen thousand, eight hundred nine".