397882809 has 27 divisors (see below), whose sum is σ = 589705389. Its totient is φ = 258513120.

The previous prime is 397882801. The next prime is 397882829. The reversal of 397882809 is 908288793.

The square root of 397882809 is 19947.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 60793209 + 337089600 = 7797^2 + 18360^2 .

It is not a de Polignac number, because 397882809 - 2³ = 397882801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (397882801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 3650247 + ... + 3650355.

Almost surely, 2^397882809 is an apocalyptic number.

397882809 is the 19947-th square number.

397882809 is the 9974-th centered octagonal number.

It is an amenable number.

397882809 is a deficient number, since it is larger than the sum of its proper divisors (191822580).

397882809 is an equidigital number, since it uses as much as digits as its factorization.

397882809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346 (or 173 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 54.

The cubic root of 397882809 is about 735.5040330068.

The spelling of 397882809 in words is "three hundred ninety-seven million, eight hundred eighty-two thousand, eight hundred nine".