398645391 has 8 divisors (see below), whose sum is σ = 531703600. Its totient is φ = 265675392.

The previous prime is 398645353. The next prime is 398645417. The reversal of 398645391 is 193546893.

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

It is not a de Polignac number, because 398645391 - 2²⁷ = 264427663 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 398645391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398645311) 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, 10666 + ... + 30183.

It is an arithmetic number, because the mean of its divisors is an integer number (66462950).

Almost surely, 2^398645391 is an apocalyptic number.

398645391 is a deficient number, since it is larger than the sum of its proper divisors (133058209).

398645391 is a wasteful number, since it uses less digits than its factorization.

398645391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44105.

The product of its digits is 699840, while the sum is 48.

The square root of 398645391 is about 19966.1060550123. The cubic root of 398645391 is about 735.9736220215.

The spelling of 398645391 in words is "three hundred ninety-eight million, six hundred forty-five thousand, three hundred ninety-one".