9997561 has 8 divisors (see below), whose sum is σ = 11484800. Its totient is φ = 8525088.

The previous prime is 9997523. The next prime is 9997573. The reversal of 9997561 is 1657999.

9997561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 9997561 - 2⁹ = 9997049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9997661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2196 + ... + 4981.

It is an arithmetic number, because the mean of its divisors is an integer number (1435600).

Almost surely, 2^9997561 is an apocalyptic number.

It is an amenable number.

9997561 is a deficient number, since it is larger than the sum of its proper divisors (1487239).

9997561 is a wasteful number, since it uses less digits than its factorization.

9997561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7383.

The product of its digits is 153090, while the sum is 46.

The square root of 9997561 is about 3161.8919968905. The cubic root of 9997561 is about 215.4259520250.

The spelling of 9997561 in words is "nine million, nine hundred ninety-seven thousand, five hundred sixty-one".