639933 has 16 divisors (see below), whose sum is σ = 1007616. Its totient is φ = 353520.

The previous prime is 639911. The next prime is 639937. The reversal of 639933 is 339936.

It is not a de Polignac number, because 639933 - 2⁸ = 639677 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 639894 and 639903.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639937) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 160 + ... + 1142.

It is an arithmetic number, because the mean of its divisors is an integer number (62976).

2⁶³⁹⁹³³ is an apocalyptic number.

It is an amenable number.

639933 is a deficient number, since it is larger than the sum of its proper divisors (367683).

639933 is a wasteful number, since it uses less digits than its factorization.

639933 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1024.

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

The square root of 639933 is about 799.9581239040. The cubic root of 639933 is about 86.1743802646.

The spelling of 639933 in words is "six hundred thirty-nine thousand, nine hundred thirty-three".