9797991 has 12 divisors (see below), whose sum is σ = 15197112. Its totient is φ = 5598768.

The previous prime is 9797959. The next prime is 9797993. The reversal of 9797991 is 1997979.

It is not a de Polignac number, because 9797991 - 2⁵ = 9797959 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9797993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33180 + ... + 33473.

It is an arithmetic number, because the mean of its divisors is an integer number (1266426).

Almost surely, 2^9797991 is an apocalyptic number.

9797991 is a deficient number, since it is larger than the sum of its proper divisors (5399121).

9797991 is a wasteful number, since it uses less digits than its factorization.

9797991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66670 (or 66663 counting only the distinct ones).

The product of its digits is 321489, while the sum is 51.

The square root of 9797991 is about 3130.1742762984. The cubic root of 9797991 is about 213.9828719514.

The spelling of 9797991 in words is "nine million, seven hundred ninety-seven thousand, nine hundred ninety-one".