1999545789 has 16 divisors (see below), whose sum is σ = 2717731520. Its totient is φ = 1307370240.

The previous prime is 1999545781. The next prime is 1999545791. The reversal of 1999545789 is 9875459991.

It is not a de Polignac number, because 1999545789 - 2³ = 1999545781 is a prime.

It is a Duffinian number.

Its product of digits (36741600) is a multiple of the sum of its prime divisors (43740).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1999545781) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24309 + ... + 67749.

It is an arithmetic number, because the mean of its divisors is an integer number (169858220).

Almost surely, 2^1999545789 is an apocalyptic number.

It is an amenable number.

1999545789 is a deficient number, since it is larger than the sum of its proper divisors (718185731).

1999545789 is a wasteful number, since it uses less digits than its factorization.

1999545789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43740.

The product of its digits is 36741600, while the sum is 66.

The square root of 1999545789 is about 44716.2810282787. The cubic root of 1999545789 is about 1259.8256643403.

The spelling of 1999545789 in words is "one billion, nine hundred ninety-nine million, five hundred forty-five thousand, seven hundred eighty-nine".