9809561 has 4 divisors (see below), whose sum is σ = 10386612. Its totient is φ = 9232512.

The previous prime is 9809549. The next prime is 9809587. The reversal of 9809561 is 1659089.

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 7425625 + 2383936 = 2725^2 + 1544^2 .

It is a cyclic number.

It is not a de Polignac number, because 9809561 - 2⁶ = 9809497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9809161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 288500 + ... + 288533.

It is an arithmetic number, because the mean of its divisors is an integer number (2596653).

Almost surely, 2^9809561 is an apocalyptic number.

It is an amenable number.

9809561 is a deficient number, since it is larger than the sum of its proper divisors (577051).

9809561 is a wasteful number, since it uses less digits than its factorization.

9809561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577050.

The product of its (nonzero) digits is 19440, while the sum is 38.

The square root of 9809561 is about 3132.0218709326. The cubic root of 9809561 is about 214.0670663526.

The spelling of 9809561 in words is "nine million, eight hundred nine thousand, five hundred sixty-one".