398757 has 8 divisors (see below), whose sum is σ = 540640. Its totient is φ = 261360.

The previous prime is 398731. The next prime is 398759. The reversal of 398757 is 757893.

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

It is not a de Polignac number, because 398757 - 2⁶ = 398693 is a prime.

It is a Duffinian number.

398757 is a lucky number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 398757.

It is not an unprimeable number, because it can be changed into a prime (398759) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 907 + ... + 1272.

It is an arithmetic number, because the mean of its divisors is an integer number (67580).

2³⁹⁸⁷⁵⁷ is an apocalyptic number.

It is an amenable number.

398757 is a deficient number, since it is larger than the sum of its proper divisors (141883).

398757 is a wasteful number, since it uses less digits than its factorization.

398757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2243.

The product of its digits is 52920, while the sum is 39.

The square root of 398757 is about 631.4720896445. The cubic root of 398757 is about 73.6042299278.

The spelling of 398757 in words is "three hundred ninety-eight thousand, seven hundred fifty-seven".