989135669809 has 15 divisors (see below), whose sum is σ = 1153979808107. Its totient is φ = 847788802896.

The previous prime is 989135669759. The next prime is 989135669831. The reversal of 989135669809 is 908966531989.

The square root of 989135669809 is 994553.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 472278200625 + 516857469184 = 687225^2 + 718928^2 .

It is not a de Polignac number, because 989135669809 - 2¹³ = 989135661617 is a prime.

It is not an unprimeable number, because it can be changed into a prime (989135669869) 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 14 ways as a sum of consecutive naturals, for example, 48722949 + ... + 48743245.

Almost surely, 2^989135669809 is an apocalyptic number.

989135669809 is the 994553-rd square number.

989135669809 is the 497277-th centered octagonal number.

It is an amenable number.

989135669809 is a deficient number, since it is larger than the sum of its proper divisors (164844138298).

989135669809 is an frugal number, since it uses more digits than its factorization.

989135669809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40622 (or 20304 counting only the distinct ones).

The product of its (nonzero) digits is 226748160, while the sum is 73.

It can be divided in two parts, 989135 and 669809, that added together give a square (1658944 = 1288²).

The spelling of 989135669809 in words is "nine hundred eighty-nine billion, one hundred thirty-five million, six hundred sixty-nine thousand, eight hundred nine".