393639 has 4 divisors (see below), whose sum is σ = 524856. Its totient is φ = 262424.

The previous prime is 393637. The next prime is 393649. The reversal of 393639 is 936393.

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

It is a cyclic number.

It is not a de Polignac number, because 393639 - 2¹ = 393637 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (393637) 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, 65604 + ... + 65609.

It is an arithmetic number, because the mean of its divisors is an integer number (131214).

2³⁹³⁶³⁹ is an apocalyptic number.

393639 is a deficient number, since it is larger than the sum of its proper divisors (131217).

393639 is a wasteful number, since it uses less digits than its factorization.

393639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131216.

The product of its digits is 13122, while the sum is 33.

The square root of 393639 is about 627.4065667492. The cubic root of 393639 is about 73.2879724066.

The spelling of 393639 in words is "three hundred ninety-three thousand, six hundred thirty-nine".