309840386 has 4 divisors (see below), whose sum is σ = 464760582. Its totient is φ = 154920192.

The previous prime is 309840299. The next prime is 309840409. The reversal of 309840386 is 683048903.

309840386 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 683048903 = 61 ⋅11197523.

It can be written as a sum of positive squares in only one way, i.e., 274068025 + 35772361 = 16555^2 + 5981^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77460095 + ... + 77460098.

Almost surely, 2^309840386 is an apocalyptic number.

309840386 is a deficient number, since it is larger than the sum of its proper divisors (154920196).

309840386 is a wasteful number, since it uses less digits than its factorization.

309840386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154920195.

The product of its (nonzero) digits is 124416, while the sum is 41.

The square root of 309840386 is about 17602.2835450404. The cubic root of 309840386 is about 676.6737691938.

The spelling of 309840386 in words is "three hundred nine million, eight hundred forty thousand, three hundred eighty-six".