997191 has 20 divisors (see below), whose sum is σ = 1605912. Its totient is φ = 613008.

The previous prime is 997163. The next prime is 997201. The reversal of 997191 is 191799.

It is not a de Polignac number, because 997191 - 2¹⁰ = 996167 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997111) 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 19 ways as a sum of consecutive naturals, for example, 580 + ... + 1526.

2⁹⁹⁷¹⁹¹ is an apocalyptic number.

997191 is a deficient number, since it is larger than the sum of its proper divisors (608721).

997191 is a wasteful number, since it uses less digits than its factorization.

997191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 972 (or 963 counting only the distinct ones).

The product of its digits is 5103, while the sum is 36.

The square root of 997191 is about 998.5945123022. The cubic root of 997191 is about 99.9062788576.

The spelling of 997191 in words is "nine hundred ninety-seven thousand, one hundred ninety-one".