729649 has 2 divisors, whose sum is σ = 729650. Its totient is φ = 729648.

The previous prime is 729643. The next prime is 729661. The reversal of 729649 is 946927.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 651249 + 78400 = 807^2 + 280^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-729649 is a prime.

It is not a weakly prime, because it can be changed into another prime (729643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 364824 + 364825.

It is an arithmetic number, because the mean of its divisors is an integer number (364825).

2⁷²⁹⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

729649 is a deficient number, since it is larger than the sum of its proper divisors (1).

729649 is an equidigital number, since it uses as much as digits as its factorization.

729649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27216, while the sum is 37.

The square root of 729649 is about 854.1949426214. The cubic root of 729649 is about 90.0266998972.

It can be divided in two parts, 729 and 649, that added together give a triangular number (1378 = T₅₂).

The spelling of 729649 in words is "seven hundred twenty-nine thousand, six hundred forty-nine".