393864 has 16 divisors (see below), whose sum is σ = 984720. Its totient is φ = 131280.

The previous prime is 393863. The next prime is 393871. The reversal of 393864 is 468393.

It is not an unprimeable number, because it can be changed into a prime (393863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8182 + ... + 8229.

It is an arithmetic number, because the mean of its divisors is an integer number (61545).

2³⁹³⁸⁶⁴ is an apocalyptic number.

It is an amenable number.

393864 is an abundant number, since it is smaller than the sum of its proper divisors (590856).

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

393864 is a wasteful number, since it uses less digits than its factorization.

393864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16420 (or 16416 counting only the distinct ones).

The product of its digits is 15552, while the sum is 33.

The square root of 393864 is about 627.5858507009. The cubic root of 393864 is about 73.3019332971.

Subtracting 393864 from its reverse (468393), we obtain a square (74529 = 273²).

The spelling of 393864 in words is "three hundred ninety-three thousand, eight hundred sixty-four".