1989436393 has 4 divisors (see below), whose sum is σ = 2273641600. Its totient is φ = 1705231188.

The previous prime is 1989436391. The next prime is 1989436403. The reversal of 1989436393 is 3936349891.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1989436393 - 2¹ = 1989436391 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1989436391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 142102593 + ... + 142102606.

It is an arithmetic number, because the mean of its divisors is an integer number (568410400).

Almost surely, 2^1989436393 is an apocalyptic number.

It is an amenable number.

1989436393 is a deficient number, since it is larger than the sum of its proper divisors (284205207).

1989436393 is an equidigital number, since it uses as much as digits as its factorization.

1989436393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284205206.

The product of its digits is 3779136, while the sum is 55.

The square root of 1989436393 is about 44603.0984686042. The cubic root of 1989436393 is about 1257.6989145262.

The spelling of 1989436393 in words is "one billion, nine hundred eighty-nine million, four hundred thirty-six thousand, three hundred ninety-three".