989432509 has 4 divisors (see below), whose sum is σ = 1065542716. Its totient is φ = 913322304.

The previous prime is 989432497. The next prime is 989432519. The reversal of 989432509 is 905234989.

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 599172484 + 390260025 = 24478^2 + 19755^2 .

It is a cyclic number.

It is not a de Polignac number, because 989432509 - 2⁹ = 989431997 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (989432519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38055084 + ... + 38055109.

It is an arithmetic number, because the mean of its divisors is an integer number (266385679).

Almost surely, 2^989432509 is an apocalyptic number.

It is an amenable number.

989432509 is a deficient number, since it is larger than the sum of its proper divisors (76110207).

989432509 is a wasteful number, since it uses less digits than its factorization.

989432509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76110206.

The product of its (nonzero) digits is 699840, while the sum is 49.

The square root of 989432509 is about 31455.2461284282. The cubic root of 989432509 is about 996.4650216525.

The spelling of 989432509 in words is "nine hundred eighty-nine million, four hundred thirty-two thousand, five hundred nine".