398718684 has 108 divisors (see below), whose sum is σ = 1262681784. Its totient is φ = 105150528.

The previous prime is 398718647. The next prime is 398718689. The reversal of 398718684 is 486817893.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 398718684.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398718689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 14239 + ... + 31625.

It is an arithmetic number, because the mean of its divisors is an integer number (11691498).

Almost surely, 2^398718684 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 398718684, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (631340892).

398718684 is an abundant number, since it is smaller than the sum of its proper divisors (863963100).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

398718684 is a wasteful number, since it uses less digits than its factorization.

398718684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17424 (or 17412 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 54.

The square root of 398718684 is about 19967.9414061640. The cubic root of 398718684 is about 736.0187234328.

The spelling of 398718684 in words is "three hundred ninety-eight million, seven hundred eighteen thousand, six hundred eighty-four".