389193985 has 4 divisors (see below), whose sum is σ = 467032788. Its totient is φ = 311355184.

The previous prime is 389193977. The next prime is 389193991. The reversal of 389193985 is 589391983.

It is a Cunningham number, because it is equal to 19728²+1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 589391983 = 17203 ⋅34261.

It can be written as a sum of positive squares in 2 ways, for example, as 140090896 + 249103089 = 11836^2 + 15783^2 .

It is a cyclic number.

It is not a de Polignac number, because 389193985 - 2³ = 389193977 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38919394 + ... + 38919403.

It is an arithmetic number, because the mean of its divisors is an integer number (116758197).

Almost surely, 2^389193985 is an apocalyptic number.

It is an amenable number.

389193985 is a deficient number, since it is larger than the sum of its proper divisors (77838803).

389193985 is an equidigital number, since it uses as much as digits as its factorization.

389193985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77838802.

The product of its digits is 2099520, while the sum is 55.

The square root of 389193985 is about 19728.0000253447. Note that the first 4 decimals coincide. The cubic root of 389193985 is about 730.1106887889.

The spelling of 389193985 in words is "three hundred eighty-nine million, one hundred ninety-three thousand, nine hundred eighty-five".