18338223551 has 4 divisors (see below), whose sum is σ = 18339041952. Its totient is φ = 18337405152.

The previous prime is 18338223517. The next prime is 18338223581. The reversal of 18338223551 is 15532283381.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18338223551 - 2⁶ = 18338223487 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18338223499 and 18338223508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18338223581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 374615 + ... + 420728.

It is an arithmetic number, because the mean of its divisors is an integer number (4584760488).

Almost surely, 2^18338223551 is an apocalyptic number.

18338223551 is a deficient number, since it is larger than the sum of its proper divisors (818401).

18338223551 is an equidigital number, since it uses as much as digits as its factorization.

18338223551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 818400.

The product of its digits is 172800, while the sum is 41.

The spelling of 18338223551 in words is "eighteen billion, three hundred thirty-eight million, two hundred twenty-three thousand, five hundred fifty-one".