639123289 has 8 divisors (see below), whose sum is σ = 730660928. Its totient is φ = 547644240.

The previous prime is 639123271. The next prime is 639123299. The reversal of 639123289 is 982321936.

639123289 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 639123289 - 2⁹ = 639122777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (639123209) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11959 + ... + 37699.

It is an arithmetic number, because the mean of its divisors is an integer number (91332616).

Almost surely, 2^639123289 is an apocalyptic number.

It is an amenable number.

639123289 is a deficient number, since it is larger than the sum of its proper divisors (91537639).

639123289 is a wasteful number, since it uses less digits than its factorization.

639123289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29295.

The product of its digits is 139968, while the sum is 43.

The square root of 639123289 is about 25280.8878206443. The cubic root of 639123289 is about 861.3801927376.

The spelling of 639123289 in words is "six hundred thirty-nine million, one hundred twenty-three thousand, two hundred eighty-nine".