398531885 has 4 divisors (see below), whose sum is σ = 478238268. Its totient is φ = 318825504.

The previous prime is 398531873. The next prime is 398531899. The reversal of 398531885 is 588135893.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 221801449 + 176730436 = 14893^2 + 13294^2 .

It is a cyclic number.

It is not a de Polignac number, because 398531885 - 2¹⁰ = 398530861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39853184 + ... + 39853193.

It is an arithmetic number, because the mean of its divisors is an integer number (119559567).

Almost surely, 2^398531885 is an apocalyptic number.

It is an amenable number.

398531885 is a deficient number, since it is larger than the sum of its proper divisors (79706383).

398531885 is an equidigital number, since it uses as much as digits as its factorization.

398531885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79706382.

The product of its digits is 1036800, while the sum is 50.

The square root of 398531885 is about 19963.2633855289. The cubic root of 398531885 is about 735.9037643204.

The spelling of 398531885 in words is "three hundred ninety-eight million, five hundred thirty-one thousand, eight hundred eighty-five".