73840309 has 2 divisors, whose sum is σ = 73840310. Its totient is φ = 73840308.

The previous prime is 73840307. The next prime is 73840321. The reversal of 73840309 is 90304837.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46539684 + 27300625 = 6822^2 + 5225^2 .

It is a cyclic number.

It is not a de Polignac number, because 73840309 - 2¹ = 73840307 is a prime.

Together with 73840307, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (73840307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36920154 + 36920155.

It is an arithmetic number, because the mean of its divisors is an integer number (36920155).

Almost surely, 2^73840309 is an apocalyptic number.

It is an amenable number.

73840309 is a deficient number, since it is larger than the sum of its proper divisors (1).

73840309 is an equidigital number, since it uses as much as digits as its factorization.

73840309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 34.

The square root of 73840309 is about 8593.0384032658. The cubic root of 73840309 is about 419.5314294394.

The spelling of 73840309 in words is "seventy-three million, eight hundred forty thousand, three hundred nine".