398986557 has 4 divisors (see below), whose sum is σ = 531982080. Its totient is φ = 265991036.

The previous prime is 398986513. The next prime is 398986571. The reversal of 398986557 is 755689893.

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 398986557 - 2⁶ = 398986493 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 398986557.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398986507) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66497757 + ... + 66497762.

It is an arithmetic number, because the mean of its divisors is an integer number (132995520).

Almost surely, 2^398986557 is an apocalyptic number.

It is an amenable number.

398986557 is a deficient number, since it is larger than the sum of its proper divisors (132995523).

398986557 is a wasteful number, since it uses less digits than its factorization.

398986557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132995522.

The product of its digits is 16329600, while the sum is 60.

The square root of 398986557 is about 19974.6478567208. The cubic root of 398986557 is about 736.1835141445.

The spelling of 398986557 in words is "three hundred ninety-eight million, nine hundred eighty-six thousand, five hundred fifty-seven".