997858 has 16 divisors (see below), whose sum is σ = 1574496. Its totient is φ = 473760.

The previous prime is 997813. The next prime is 997877. The reversal of 997858 is 858799.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3385 + ... + 3667.

It is an arithmetic number, because the mean of its divisors is an integer number (98406).

2⁹⁹⁷⁸⁵⁸ is an apocalyptic number.

997858 is a deficient number, since it is larger than the sum of its proper divisors (576638).

997858 is a wasteful number, since it uses less digits than its factorization.

997858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 369.

The product of its digits is 181440, while the sum is 46.

The square root of 997858 is about 998.9284258644. The cubic root of 997858 is about 99.9285489596.

The spelling of 997858 in words is "nine hundred ninety-seven thousand, eight hundred fifty-eight".