18826309 has 4 divisors (see below), whose sum is σ = 19053216. Its totient is φ = 18599404.

The previous prime is 18826279. The next prime is 18826333. The reversal of 18826309 is 90362881.

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: 90362881 = 7 ⋅12908983.

It is a cyclic number.

It is not a de Polignac number, because 18826309 - 2⁵ = 18826277 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 (18826349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113329 + ... + 113494.

It is an arithmetic number, because the mean of its divisors is an integer number (4763304).

Almost surely, 2^18826309 is an apocalyptic number.

It is an amenable number.

18826309 is a deficient number, since it is larger than the sum of its proper divisors (226907).

18826309 is an equidigital number, since it uses as much as digits as its factorization.

18826309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226906.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 18826309 is about 4338.9294762649. The cubic root of 18826309 is about 266.0245563099.

The spelling of 18826309 in words is "eighteen million, eight hundred twenty-six thousand, three hundred nine".