997128 has 48 divisors (see below), whose sum is σ = 2948400. Its totient is φ = 301920.

The previous prime is 997123. The next prime is 997141. The reversal of 997128 is 821799.

It is a happy number.

997128 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 997092 and 997101.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 997128.

It is not an unprimeable number, because it can be changed into a prime (997121) by changing a digit.

997128 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 163 + ... + 1421.

It is an arithmetic number, because the mean of its divisors is an integer number (61425).

2⁹⁹⁷¹²⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 997128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1474200).

997128 is an abundant number, since it is smaller than the sum of its proper divisors (1951272).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

997128 is a wasteful number, since it uses less digits than its factorization.

997128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1282 (or 1275 counting only the distinct ones).

The product of its digits is 9072, while the sum is 36.

The square root of 997128 is about 998.5629674688. The cubic root of 997128 is about 99.9041748714.

It can be divided in two parts, 9971 and 28, that added together give a palindrome (9999).

The spelling of 997128 in words is "nine hundred ninety-seven thousand, one hundred twenty-eight".