309513649 has 9 divisors (see below), whose sum is σ = 315119169. Its totient is φ = 304007040.

The previous prime is 309513647. The next prime is 309513653. The reversal of 309513649 is 946315903.

The square root of 309513649 is 17593.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 32890225 + 276623424 = 5735^2 + 16632^2 .

It is not a de Polignac number, because 309513649 - 2¹ = 309513647 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (309513643) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1284169 + ... + 1284409.

It is an arithmetic number, because the mean of its divisors is an integer number (35013241).

Almost surely, 2^309513649 is an apocalyptic number.

309513649 is the 17593-rd square number.

309513649 is the 8797-th centered octagonal number.

It is an amenable number.

309513649 is a deficient number, since it is larger than the sum of its proper divisors (5605520).

309513649 is an frugal number, since it uses more digits than its factorization.

309513649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 628 (or 314 counting only the distinct ones).

The product of its (nonzero) digits is 87480, while the sum is 40.

The cubic root of 309513649 is about 676.4358271974.

The spelling of 309513649 in words is "three hundred nine million, five hundred thirteen thousand, six hundred forty-nine".