9971609 has 4 divisors (see below), whose sum is σ = 10135140. Its totient is φ = 9808080.

The previous prime is 9971603. The next prime is 9971641. The reversal of 9971609 is 9061799.

It is a happy number.

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 1974025 + 7997584 = 1405^2 + 2828^2 .

It is a cyclic number.

It is not a de Polignac number, because 9971609 - 2¹² = 9967513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9971603) by changing a digit.

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, 81674 + ... + 81795.

It is an arithmetic number, because the mean of its divisors is an integer number (2533785).

Almost surely, 2^9971609 is an apocalyptic number.

It is an amenable number.

9971609 is a deficient number, since it is larger than the sum of its proper divisors (163531).

9971609 is a wasteful number, since it uses less digits than its factorization.

9971609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163530.

The product of its (nonzero) digits is 30618, while the sum is 41.

The square root of 9971609 is about 3157.7854581969. The cubic root of 9971609 is about 215.2393872274.

The spelling of 9971609 in words is "nine million, nine hundred seventy-one thousand, six hundred nine".