729639 has 6 divisors (see below), whose sum is σ = 1053936. Its totient is φ = 486420.

The previous prime is 729637. The next prime is 729643. The reversal of 729639 is 936927.

It is not a de Polignac number, because 729639 - 2¹ = 729637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (729637) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 40527 + ... + 40544.

It is an arithmetic number, because the mean of its divisors is an integer number (175656).

2⁷²⁹⁶³⁹ is an apocalyptic number.

729639 is a deficient number, since it is larger than the sum of its proper divisors (324297).

729639 is a wasteful number, since it uses less digits than its factorization.

729639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81077 (or 81074 counting only the distinct ones).

The product of its digits is 20412, while the sum is 36.

The square root of 729639 is about 854.1890891366. The cubic root of 729639 is about 90.0262886168.

It can be divided in two parts, 7 and 29639, that added together give a triangular number (29646 = T₂₄₃).

The spelling of 729639 in words is "seven hundred twenty-nine thousand, six hundred thirty-nine".