309648349 has 4 divisors (see below), whose sum is σ = 313379136. Its totient is φ = 305917564.

The previous prime is 309648331. The next prime is 309648371. The reversal of 309648349 is 943846903.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 943846903 = 47 ⋅20081849.

It is a cyclic number.

It is not a de Polignac number, because 309648349 - 2⁷ = 309648221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 309648299 and 309648308.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (309648389) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1865269 + ... + 1865434.

It is an arithmetic number, because the mean of its divisors is an integer number (78344784).

Almost surely, 2^309648349 is an apocalyptic number.

It is an amenable number.

309648349 is a deficient number, since it is larger than the sum of its proper divisors (3730787).

309648349 is an equidigital number, since it uses as much as digits as its factorization.

309648349 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3730786.

The product of its (nonzero) digits is 559872, while the sum is 46.

The square root of 309648349 is about 17596.8278107163. The cubic root of 309648349 is about 676.5339410087.

The spelling of 309648349 in words is "three hundred nine million, six hundred forty-eight thousand, three hundred forty-nine".