9917561 has 8 divisors (see below), whose sum is σ = 10158720. Its totient is φ = 9679392.

The previous prime is 9917549. The next prime is 9917569. The reversal of 9917561 is 1657199.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9917561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9917569) 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 7 ways as a sum of consecutive naturals, for example, 6860 + ... + 8178.

It is an arithmetic number, because the mean of its divisors is an integer number (1269840).

Almost surely, 2^9917561 is an apocalyptic number.

It is an amenable number.

9917561 is a deficient number, since it is larger than the sum of its proper divisors (241159).

9917561 is a wasteful number, since it uses less digits than its factorization.

9917561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1495.

The product of its digits is 17010, while the sum is 38.

The square root of 9917561 is about 3149.2159341652. The cubic root of 9917561 is about 214.8498031568.

The spelling of 9917561 in words is "nine million, nine hundred seventeen thousand, five hundred sixty-one".