398396257 has 4 divisors (see below), whose sum is σ = 455310016. Its totient is φ = 341482500.

The previous prime is 398396239. The next prime is 398396267. The reversal of 398396257 is 752693893.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 398396257 - 2¹¹ = 398394209 is a prime.

It is a super-2 number, since 2×398396257² = 317439155183220098, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (398396227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28456869 + ... + 28456882.

It is an arithmetic number, because the mean of its divisors is an integer number (113827504).

Almost surely, 2^398396257 is an apocalyptic number.

It is an amenable number.

398396257 is a deficient number, since it is larger than the sum of its proper divisors (56913759).

398396257 is an equidigital number, since it uses as much as digits as its factorization.

398396257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56913758.

The product of its digits is 2449440, while the sum is 52.

The square root of 398396257 is about 19959.8661568659. The cubic root of 398396257 is about 735.8202741540.

The spelling of 398396257 in words is "three hundred ninety-eight million, three hundred ninety-six thousand, two hundred fifty-seven".