398705 has 8 divisors (see below), whose sum is σ = 499392. Its totient is φ = 305008.

The previous prime is 398693. The next prime is 398711. The reversal of 398705 is 507893.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-398705 is a prime.

It is an Ulam number.

It is a Duffinian 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, 1619 + ... + 1848.

It is an arithmetic number, because the mean of its divisors is an integer number (62424).

2³⁹⁸⁷⁰⁵ is an apocalyptic number.

It is an amenable number.

398705 is a deficient number, since it is larger than the sum of its proper divisors (100687).

398705 is a wasteful number, since it uses less digits than its factorization.

398705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3495.

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 398705 is about 631.4309146692. The cubic root of 398705 is about 73.6010303298.

The spelling of 398705 in words is "three hundred ninety-eight thousand, seven hundred five".