639239933 has 16 divisors (see below), whose sum is σ = 735459840. Its totient is φ = 551577600.

The previous prime is 639239929. The next prime is 639239947. The reversal of 639239933 is 339932936.

It is a happy number.

639239933 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 639239933 - 2² = 639239929 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639239033) 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, 21908 + ... + 41933.

It is an arithmetic number, because the mean of its divisors is an integer number (45966240).

Almost surely, 2^639239933 is an apocalyptic number.

It is an amenable number.

639239933 is a deficient number, since it is larger than the sum of its proper divisors (96219907).

639239933 is a wasteful number, since it uses less digits than its factorization.

639239933 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63908.

The product of its digits is 708588, while the sum is 47.

The square root of 639239933 is about 25283.1946755152. The cubic root of 639239933 is about 861.4325919753.

The spelling of 639239933 in words is "six hundred thirty-nine million, two hundred thirty-nine thousand, nine hundred thirty-three".