729818 has 4 divisors (see below), whose sum is σ = 1094730. Its totient is φ = 364908.

The previous prime is 729791. The next prime is 729821. The reversal of 729818 is 818927.

It is a happy number.

729818 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 818927 = 31 ⋅26417.

It can be written as a sum of positive squares in only one way, i.e., 727609 + 2209 = 853^2 + 47^2 .

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

729818 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 182453 + ... + 182456.

2⁷²⁹⁸¹⁸ is an apocalyptic number.

729818 is a deficient number, since it is larger than the sum of its proper divisors (364912).

729818 is a wasteful number, since it uses less digits than its factorization.

729818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 364911.

The product of its digits is 8064, while the sum is 35.

The square root of 729818 is about 854.2938604485. The cubic root of 729818 is about 90.0336499685.

The spelling of 729818 in words is "seven hundred twenty-nine thousand, eight hundred eighteen".