9991097 has 4 divisors (see below), whose sum is σ = 10094196. Its totient is φ = 9888000.

The previous prime is 9991067. The next prime is 9991123. The reversal of 9991097 is 7901999.

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 2128681 + 7862416 = 1459^2 + 2804^2 .

It is a cyclic number.

It is not a de Polignac number, because 9991097 - 2¹² = 9987001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9991027) 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, 51404 + ... + 51597.

It is an arithmetic number, because the mean of its divisors is an integer number (2523549).

Almost surely, 2^9991097 is an apocalyptic number.

9991097 is a gapful number since it is divisible by the number (97) formed by its first and last digit.

It is an amenable number.

9991097 is a deficient number, since it is larger than the sum of its proper divisors (103099).

9991097 is a wasteful number, since it uses less digits than its factorization.

9991097 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103098.

The product of its (nonzero) digits is 45927, while the sum is 44.

The square root of 9991097 is about 3160.8696588123. The cubic root of 9991097 is about 215.3795135794.

The spelling of 9991097 in words is "nine million, nine hundred ninety-one thousand, ninety-seven".