309193849 has 2 divisors, whose sum is σ = 309193850. Its totient is φ = 309193848.

The previous prime is 309193831. The next prime is 309193883. The reversal of 309193849 is 948391903.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 217857600 + 91336249 = 14760^2 + 9557^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-309193849 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 309193799 and 309193808.

It is not a weakly prime, because it can be changed into another prime (309103849) 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, 154596924 + 154596925.

It is an arithmetic number, because the mean of its divisors is an integer number (154596925).

Almost surely, 2^309193849 is an apocalyptic number.

It is an amenable number.

309193849 is a deficient number, since it is larger than the sum of its proper divisors (1).

309193849 is an equidigital number, since it uses as much as digits as its factorization.

309193849 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 209952, while the sum is 46.

The square root of 309193849 is about 17583.9088089082. The cubic root of 309193849 is about 676.2027747666.

The spelling of 309193849 in words is "three hundred nine million, one hundred ninety-three thousand, eight hundred forty-nine".