9967591 has 4 divisors (see below), whose sum is σ = 9991800. Its totient is φ = 9943384.

The previous prime is 9967549. The next prime is 9967597. The reversal of 9967591 is 1957699.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1957699 = 79 ⋅24781.

It is a cyclic number.

It is not a de Polignac number, because 9967591 - 2⁹ = 9967079 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9967597) 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, 11476 + ... + 12313.

It is an arithmetic number, because the mean of its divisors is an integer number (2497950).

Almost surely, 2^9967591 is an apocalyptic number.

9967591 is a deficient number, since it is larger than the sum of its proper divisors (24209).

9967591 is a wasteful number, since it uses less digits than its factorization.

9967591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24208.

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

The square root of 9967591 is about 3157.1491887461. The cubic root of 9967591 is about 215.2104735370.

The spelling of 9967591 in words is "nine million, nine hundred sixty-seven thousand, five hundred ninety-one".