309012073 has 2 divisors, whose sum is σ = 309012074. Its totient is φ = 309012072.

The previous prime is 309012019. The next prime is 309012079. The reversal of 309012073 is 370210903.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 306845289 + 2166784 = 17517^2 + 1472^2 .

It is a cyclic number.

It is not a de Polignac number, because 309012073 - 2¹³ = 309003881 is a prime.

It is a super-2 number, since 2×309012073² = 190976922519514658, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (309012079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 154506036 + 154506037.

It is an arithmetic number, because the mean of its divisors is an integer number (154506037).

Almost surely, 2^309012073 is an apocalyptic number.

It is an amenable number.

309012073 is a deficient number, since it is larger than the sum of its proper divisors (1).

309012073 is an equidigital number, since it uses as much as digits as its factorization.

309012073 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1134, while the sum is 25.

The square root of 309012073 is about 17578.7392323796. The cubic root of 309012073 is about 676.0702349034.

Adding to 309012073 its reverse (370210903), we get a palindrome (679222976).

The spelling of 309012073 in words is "three hundred nine million, twelve thousand, seventy-three".