993639 has 4 divisors (see below), whose sum is σ = 1324856. Its totient is φ = 662424.

The previous prime is 993617. The next prime is 993647. The reversal of 993639 is 936399.

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

It is not a de Polignac number, because 993639 - 2¹³ = 985447 is a prime.

It is a D-number.

It is a Duffinian number.

993639 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 993597 and 993606.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 993639.

It is not an unprimeable number, because it can be changed into a prime (993679) 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, 165604 + ... + 165609.

It is an arithmetic number, because the mean of its divisors is an integer number (331214).

2⁹⁹³⁶³⁹ is an apocalyptic number.

993639 is a deficient number, since it is larger than the sum of its proper divisors (331217).

993639 is a wasteful number, since it uses less digits than its factorization.

993639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331216.

The product of its digits is 39366, while the sum is 39.

The square root of 993639 is about 996.8144260593. The cubic root of 993639 is about 99.7875154898.

The spelling of 993639 in words is "nine hundred ninety-three thousand, six hundred thirty-nine".