18844550369 has 4 divisors (see below), whose sum is σ = 19056286980. Its totient is φ = 18632813760.

The previous prime is 18844550363. The next prime is 18844550383. The reversal of 18844550369 is 96305544881.

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

It can be written as a sum of positive squares in 2 ways, for example, as 9070657600 + 9773892769 = 95240^2 + 98863^2 .

It is a cyclic number.

It is not a de Polignac number, because 18844550369 - 2¹⁶ = 18844484833 is a prime.

It is a super-2 number, since 2×18844550369² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18844550369.

It is not an unprimeable number, because it can be changed into a prime (18844550363) 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, 105868172 + ... + 105868349.

It is an arithmetic number, because the mean of its divisors is an integer number (4764071745).

Almost surely, 2^18844550369 is an apocalyptic number.

It is an amenable number.

18844550369 is a deficient number, since it is larger than the sum of its proper divisors (211736611).

18844550369 is an equidigital number, since it uses as much as digits as its factorization.

18844550369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211736610.

The product of its (nonzero) digits is 4147200, while the sum is 53.

The spelling of 18844550369 in words is "eighteen billion, eight hundred forty-four million, five hundred fifty thousand, three hundred sixty-nine".