1844889989 has 4 divisors (see below), whose sum is σ = 1865619180. Its totient is φ = 1824160800.

The previous prime is 1844889973. The next prime is 1844890027. The reversal of 1844889989 is 9899884481.

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 369024100 + 1475865889 = 19210^2 + 38417^2 .

It is a cyclic number.

It is not a de Polignac number, because 1844889989 - 2⁴ = 1844889973 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 (1844889289) 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, 10364462 + ... + 10364639.

It is an arithmetic number, because the mean of its divisors is an integer number (466404795).

Almost surely, 2^1844889989 is an apocalyptic number.

It is an amenable number.

1844889989 is a deficient number, since it is larger than the sum of its proper divisors (20729191).

1844889989 is an equidigital number, since it uses as much as digits as its factorization.

1844889989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20729190.

The product of its digits is 47775744, while the sum is 68.

The square root of 1844889989 is about 42952.1825871515. The cubic root of 1844889989 is about 1226.4697037830.

The spelling of 1844889989 in words is "one billion, eight hundred forty-four million, eight hundred eighty-nine thousand, nine hundred eighty-nine".