398905887 has 8 divisors (see below), whose sum is σ = 531980080. Its totient is φ = 265884480.

The previous prime is 398905849. The next prime is 398905907. The reversal of 398905887 is 788509893.

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

It is not a de Polignac number, because 398905887 - 2⁶ = 398905823 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398905487) 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 7 ways as a sum of consecutive naturals, for example, 10539 + ... + 30147.

It is an arithmetic number, because the mean of its divisors is an integer number (66497510).

Almost surely, 2^398905887 is an apocalyptic number.

398905887 is a deficient number, since it is larger than the sum of its proper divisors (133074193).

398905887 is a wasteful number, since it uses less digits than its factorization.

398905887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26393.

The product of its (nonzero) digits is 4354560, while the sum is 57.

The square root of 398905887 is about 19972.6284449494. The cubic root of 398905887 is about 736.1338951569.

The spelling of 398905887 in words is "three hundred ninety-eight million, nine hundred five thousand, eight hundred eighty-seven".