398645 has 8 divisors (see below), whose sum is σ = 515256. Its totient is φ = 294336.

The previous prime is 398627. The next prime is 398669. The reversal of 398645 is 546893.

It can be written as a sum of positive squares in 4 ways, for example, as 69169 + 329476 = 263^2 + 574^2 .

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 398645 - 2⁶ = 398581 is a prime.

It is a Duffinian number.

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, 3002 + ... + 3131.

It is an arithmetic number, because the mean of its divisors is an integer number (64407).

2³⁹⁸⁶⁴⁵ is an apocalyptic number.

It is an amenable number.

398645 is a deficient number, since it is larger than the sum of its proper divisors (116611).

398645 is a wasteful number, since it uses less digits than its factorization.

398645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6151.

The product of its digits is 25920, while the sum is 35.

The square root of 398645 is about 631.3834017457. The cubic root of 398645 is about 73.5973381402.

The spelling of 398645 in words is "three hundred ninety-eight thousand, six hundred forty-five".