309806209061 has 2 divisors, whose sum is σ = 309806209062. Its totient is φ = 309806209060.

The previous prime is 309806209039. The next prime is 309806209087. The reversal of 309806209061 is 160902608903.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 205667692036 + 104138517025 = 453506^2 + 322705^2 .

It is an emirp because it is prime and its reverse (160902608903) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 309806209061 - 2¹⁴ = 309806192677 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (309806209261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 154903104530 + 154903104531.

It is an arithmetic number, because the mean of its divisors is an integer number (154903104531).

Almost surely, 2^309806209061 is an apocalyptic number.

It is an amenable number.

309806209061 is a deficient number, since it is larger than the sum of its proper divisors (1).

309806209061 is an equidigital number, since it uses as much as digits as its factorization.

309806209061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 139968, while the sum is 44.

The spelling of 309806209061 in words is "three hundred nine billion, eight hundred six million, two hundred nine thousand, sixty-one".