309426391 has 2 divisors, whose sum is σ = 309426392. Its totient is φ = 309426390.

The previous prime is 309426373. The next prime is 309426443. The reversal of 309426391 is 193624903.

It is a weak prime.

It is an emirp because it is prime and its reverse (193624903) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 309426391 - 2¹¹ = 309424343 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 309426391.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (309426361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 154713195 + 154713196.

It is an arithmetic number, because the mean of its divisors is an integer number (154713196).

Almost surely, 2^309426391 is an apocalyptic number.

309426391 is a deficient number, since it is larger than the sum of its proper divisors (1).

309426391 is an equidigital number, since it uses as much as digits as its factorization.

309426391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34992, while the sum is 37.

The square root of 309426391 is about 17590.5199184106. The cubic root of 309426391 is about 676.3722543574.

The spelling of 309426391 in words is "three hundred nine million, four hundred twenty-six thousand, three hundred ninety-one".