989828509 has 2 divisors, whose sum is σ = 989828510. Its totient is φ = 989828508.

The previous prime is 989828473. The next prime is 989828557. The reversal of 989828509 is 905828989.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 686964100 + 302864409 = 26210^2 + 17403^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-989828509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (989828569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494914254 + 494914255.

It is an arithmetic number, because the mean of its divisors is an integer number (494914255).

Almost surely, 2^989828509 is an apocalyptic number.

It is an amenable number.

989828509 is a deficient number, since it is larger than the sum of its proper divisors (1).

989828509 is an equidigital number, since it uses as much as digits as its factorization.

989828509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3732480, while the sum is 58.

The square root of 989828509 is about 31461.5401561971. The cubic root of 989828509 is about 996.5979421274.

The spelling of 989828509 in words is "nine hundred eighty-nine million, eight hundred twenty-eight thousand, five hundred nine".