749509309 has 2 divisors, whose sum is σ = 749509310. Its totient is φ = 749509308.

The previous prime is 749509301. The next prime is 749509357. The reversal of 749509309 is 903905947.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 391921209 + 357588100 = 19797^2 + 18910^2 .

It is a cyclic number.

It is not a de Polignac number, because 749509309 - 2³ = 749509301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (749509301) 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, 374754654 + 374754655.

It is an arithmetic number, because the mean of its divisors is an integer number (374754655).

Almost surely, 2^749509309 is an apocalyptic number.

It is an amenable number.

749509309 is a deficient number, since it is larger than the sum of its proper divisors (1).

749509309 is an equidigital number, since it uses as much as digits as its factorization.

749509309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 306180, while the sum is 46.

The square root of 749509309 is about 27377.1676584704. The cubic root of 749509309 is about 908.3621099170.

The spelling of 749509309 in words is "seven hundred forty-nine million, five hundred nine thousand, three hundred nine".