997658 has 16 divisors (see below), whose sum is σ = 1572480. Its totient is φ = 474096.

The previous prime is 997651. The next prime is 997663. The reversal of 997658 is 856799.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 997658.

It is not an unprimeable number, because it can be changed into a prime (997651) 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 7 ways as a sum of consecutive naturals, for example, 5891 + ... + 6057.

It is an arithmetic number, because the mean of its divisors is an integer number (98280).

2⁹⁹⁷⁶⁵⁸ is an apocalyptic number.

997658 is a deficient number, since it is larger than the sum of its proper divisors (574822).

997658 is a wasteful number, since it uses less digits than its factorization.

997658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 301.

The product of its digits is 136080, while the sum is 44.

The square root of 997658 is about 998.8283135755. The cubic root of 997658 is about 99.9218723099.

The spelling of 997658 in words is "nine hundred ninety-seven thousand, six hundred fifty-eight".