639429 has 8 divisors (see below), whose sum is σ = 974400. Its totient is φ = 365376.

The previous prime is 639391. The next prime is 639433. The reversal of 639429 is 924936.

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

It is not a de Polignac number, because 639429 - 2¹² = 635333 is a prime.

It is a d-powerful number, because it can be written as 6⁶ + 3⁷ + 4³ + 9⁵ + 2⁵ + 9⁶ .

It is a self number, because there is not a number n which added to its sum of digits gives 639429.

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 639429.

It is not an unprimeable number, because it can be changed into a prime (639439) 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, 15204 + ... + 15245.

It is an arithmetic number, because the mean of its divisors is an integer number (121800).

2⁶³⁹⁴²⁹ is an apocalyptic number.

It is an amenable number.

639429 is a deficient number, since it is larger than the sum of its proper divisors (334971).

639429 is a wasteful number, since it uses less digits than its factorization.

639429 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30459.

The product of its digits is 11664, while the sum is 33.

The square root of 639429 is about 799.6430453646. The cubic root of 639429 is about 86.1517511796.

The spelling of 639429 in words is "six hundred thirty-nine thousand, four hundred twenty-nine".