997440 has 56 divisors (see below), whose sum is σ = 3169920. Its totient is φ = 265728.

The previous prime is 997439. The next prime is 997453. The reversal of 997440 is 44799.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is a nialpdrome in base 10.

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, 441 + ... + 1479.

2⁹⁹⁷⁴⁴⁰ 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 997440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1584960).

997440 is an abundant number, since it is smaller than the sum of its proper divisors (2172480).

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

997440 is a wasteful number, since it uses less digits than its factorization.

997440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1059 (or 1049 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 997440 is about 998.7191797497. The cubic root of 997440 is about 99.9145937451.

The spelling of 997440 in words is "nine hundred ninety-seven thousand, four hundred forty".