997540 has 12 divisors (see below), whose sum is σ = 2094876. Its totient is φ = 399008.

The previous prime is 997511. The next prime is 997541. The reversal of 997540 is 45799.

997540 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 147456 + 850084 = 384^2 + 922^2 .

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 997496 and 997505.

It is not an unprimeable number, because it can be changed into a prime (997541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24919 + ... + 24958.

It is an arithmetic number, because the mean of its divisors is an integer number (174573).

2⁹⁹⁷⁵⁴⁰ is an apocalyptic number.

It is an amenable number.

997540 is an abundant number, since it is smaller than the sum of its proper divisors (1097336).

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

997540 is a wasteful number, since it uses less digits than its factorization.

997540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49886 (or 49884 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 34.

The square root of 997540 is about 998.7692426181. The cubic root of 997540 is about 99.9179326680.

The spelling of 997540 in words is "nine hundred ninety-seven thousand, five hundred forty".