729551309 has 2 divisors, whose sum is σ = 729551310. Its totient is φ = 729551308.

The previous prime is 729551293. The next prime is 729551323. The reversal of 729551309 is 903155927.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 370562500 + 358988809 = 19250^2 + 18947^2 .

It is a cyclic number.

It is not a de Polignac number, because 729551309 - 2⁴ = 729551293 is a prime.

It is a super-2 number, since 2×729551309² = 1064490224927226962, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (729551509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 364775654 + 364775655.

It is an arithmetic number, because the mean of its divisors is an integer number (364775655).

Almost surely, 2^729551309 is an apocalyptic number.

It is an amenable number.

729551309 is a deficient number, since it is larger than the sum of its proper divisors (1).

729551309 is an equidigital number, since it uses as much as digits as its factorization.

729551309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 85050, while the sum is 41.

The square root of 729551309 is about 27010.2074964262. The cubic root of 729551309 is about 900.2268189637.

The spelling of 729551309 in words is "seven hundred twenty-nine million, five hundred fifty-one thousand, three hundred nine".