729161 has 4 divisors (see below), whose sum is σ = 740112. Its totient is φ = 718212.

The previous prime is 729143. The next prime is 729173. The reversal of 729161 is 161927.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 161927 = 193 ⋅839.

It is a cyclic number.

It is not a de Polignac number, because 729161 - 2¹⁸ = 467017 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 729161.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 729161.

It is not an unprimeable number, because it can be changed into a prime (729191) by changing a digit.

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, 5375 + ... + 5508.

It is an arithmetic number, because the mean of its divisors is an integer number (185028).

2⁷²⁹¹⁶¹ is an apocalyptic number.

It is an amenable number.

729161 is a deficient number, since it is larger than the sum of its proper divisors (10951).

729161 is a wasteful number, since it uses less digits than its factorization.

729161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10950.

The product of its digits is 756, while the sum is 26.

The square root of 729161 is about 853.9092457633. The cubic root of 729161 is about 90.0066250267.

The spelling of 729161 in words is "seven hundred twenty-nine thousand, one hundred sixty-one".