397540 has 48 divisors (see below), whose sum is σ = 987840. Its totient is φ = 132480.

The previous prime is 397519. The next prime is 397541. The reversal of 397540 is 45793.

397540 = T₁₇₉ + T₁₈₀ + ... + T₂₀₀.

It is a Smith number, since the sum of its digits (28) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 397499 and 397508.

It is not an unprimeable number, because it can be changed into a prime (397541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2791 + ... + 2929.

It is an arithmetic number, because the mean of its divisors is an integer number (20580).

2³⁹⁷⁵⁴⁰ 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 397540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (493920).

397540 is an abundant number, since it is smaller than the sum of its proper divisors (590300).

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

397540 is a wasteful number, since it uses less digits than its factorization.

397540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172 (or 170 counting only the distinct ones).

The product of its (nonzero) digits is 3780, while the sum is 28.

The square root of 397540 is about 630.5077319114. The cubic root of 397540 is about 73.5292739762.

The spelling of 397540 in words is "three hundred ninety-seven thousand, five hundred forty".