729920 has 28 divisors (see below), whose sum is σ = 1738884. Its totient is φ = 291840.

The previous prime is 729919. The next prime is 729931. The reversal of 729920 is 29927.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 350464 + 379456 = 592^2 + 616^2 .

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 729920.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 821 + ... + 1460.

It is an arithmetic number, because the mean of its divisors is an integer number (62103).

2⁷²⁹⁹²⁰ is an apocalyptic number.

It is an amenable number.

729920 is an abundant number, since it is smaller than the sum of its proper divisors (1008964).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

729920 is a wasteful number, since it uses less digits than its factorization.

729920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2298 (or 2288 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 29.

The square root of 729920 is about 854.3535567902. The cubic root of 729920 is about 90.0378441670.

The spelling of 729920 in words is "seven hundred twenty-nine thousand, nine hundred twenty".