997340491 has 4 divisors (see below), whose sum is σ = 1139817712. Its totient is φ = 854863272.

The previous prime is 997340471. The next prime is 997340501. The reversal of 997340491 is 194043799.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 194043799 = 37 ⋅5244427.

It is a cyclic number.

It is not a de Polignac number, because 997340491 - 2²¹ = 995243339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (997340471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71238600 + ... + 71238613.

It is an arithmetic number, because the mean of its divisors is an integer number (284954428).

Almost surely, 2^997340491 is an apocalyptic number.

997340491 is a deficient number, since it is larger than the sum of its proper divisors (142477221).

997340491 is a wasteful number, since it uses less digits than its factorization.

997340491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142477220.

The product of its (nonzero) digits is 244944, while the sum is 46.

The square root of 997340491 is about 31580.6980765150. The cubic root of 997340491 is about 999.1127099492.

The spelling of 997340491 in words is "nine hundred ninety-seven million, three hundred forty thousand, four hundred ninety-one".