397840369 has 8 divisors (see below), whose sum is σ = 400445928. Its totient is φ = 395243520.

The previous prime is 397840367. The next prime is 397840393. The reversal of 397840369 is 963048793.

It can be written as a sum of positive squares in 4 ways, for example, as 99760144 + 298080225 = 9988^2 + 17265^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 397840369 - 2¹ = 397840367 is a prime.

It is a super-2 number, since 2×397840369² = 316553918412112322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (397840367) 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 7 ways as a sum of consecutive naturals, for example, 106359 + ... + 110035.

It is an arithmetic number, because the mean of its divisors is an integer number (50055741).

Almost surely, 2^397840369 is an apocalyptic number.

It is an amenable number.

397840369 is a deficient number, since it is larger than the sum of its proper divisors (2605559).

397840369 is a wasteful number, since it uses less digits than its factorization.

397840369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4355.

The product of its (nonzero) digits is 979776, while the sum is 49.

The square root of 397840369 is about 19945.9361525099. The cubic root of 397840369 is about 735.4778813357.

The spelling of 397840369 in words is "three hundred ninety-seven million, eight hundred forty thousand, three hundred sixty-nine".