729215281 has 2 divisors, whose sum is σ = 729215282. Its totient is φ = 729215280.

The previous prime is 729215273. The next prime is 729215303. The reversal of 729215281 is 182512927.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 664814656 + 64400625 = 25784^2 + 8025^2 .

It is an emirp because it is prime and its reverse (182512927) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 729215281 - 2³ = 729215273 is a prime.

It is a super-2 number, since 2×729215281² = 1063509852087817922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 729215281.

It is not a weakly prime, because it can be changed into another prime (729215881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 364607640 + 364607641.

It is an arithmetic number, because the mean of its divisors is an integer number (364607641).

Almost surely, 2^729215281 is an apocalyptic number.

It is an amenable number.

729215281 is a deficient number, since it is larger than the sum of its proper divisors (1).

729215281 is an equidigital number, since it uses as much as digits as its factorization.

729215281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20160, while the sum is 37.

The square root of 729215281 is about 27003.9863909016. The cubic root of 729215281 is about 900.0885842847.

The spelling of 729215281 in words is "seven hundred twenty-nine million, two hundred fifteen thousand, two hundred eighty-one".