997675391 has 2 divisors, whose sum is σ = 997675392. Its totient is φ = 997675390.

The previous prime is 997675381. The next prime is 997675403. The reversal of 997675391 is 193576799.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 997675391 - 2¹⁰ = 997674367 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (997675381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498837695 + 498837696.

It is an arithmetic number, because the mean of its divisors is an integer number (498837696).

Almost surely, 2^997675391 is an apocalyptic number.

997675391 is a deficient number, since it is larger than the sum of its proper divisors (1).

997675391 is an equidigital number, since it uses as much as digits as its factorization.

997675391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3214890, while the sum is 56.

The square root of 997675391 is about 31585.9999208510. Note that the first 4 decimals coincide. The cubic root of 997675391 is about 999.2245291337.

The spelling of 997675391 in words is "nine hundred ninety-seven million, six hundred seventy-five thousand, three hundred ninety-one".