1985443189 has 8 divisors (see below), whose sum is σ = 2020194360. Its totient is φ = 1950763200.

The previous prime is 1985443181. The next prime is 1985443217. The reversal of 1985443189 is 9813445891.

It can be written as a sum of positive squares in 4 ways, for example, as 103184964 + 1882258225 = 10158^2 + 43385^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1985443189 - 2³ = 1985443181 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 (1985443181) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40107 + ... + 74695.

It is an arithmetic number, because the mean of its divisors is an integer number (252524295).

Almost surely, 2^1985443189 is an apocalyptic number.

It is an amenable number.

1985443189 is a deficient number, since it is larger than the sum of its proper divisors (34751171).

1985443189 is an equidigital number, since it uses as much as digits as its factorization.

1985443189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35591.

The product of its digits is 1244160, while the sum is 52.

The square root of 1985443189 is about 44558.3122323995. The cubic root of 1985443189 is about 1256.8568649335.

The spelling of 1985443189 in words is "one billion, nine hundred eighty-five million, four hundred forty-three thousand, one hundred eighty-nine".