20345884309 has 2 divisors, whose sum is σ = 20345884310. Its totient is φ = 20345884308.

The previous prime is 20345884289. The next prime is 20345884367. The reversal of 20345884309 is 90348854302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20284026084 + 61858225 = 142422^2 + 7865^2 .

It is a cyclic number.

It is not a de Polignac number, because 20345884309 - 2¹⁵ = 20345851541 is a prime.

It is a super-3 number, since 3×20345884309³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20345884369) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10172942154 + 10172942155.

It is an arithmetic number, because the mean of its divisors is an integer number (10172942155).

Almost surely, 2^20345884309 is an apocalyptic number.

It is an amenable number.

20345884309 is a deficient number, since it is larger than the sum of its proper divisors (1).

20345884309 is an equidigital number, since it uses as much as digits as its factorization.

20345884309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 829440, while the sum is 46.

The spelling of 20345884309 in words is "twenty billion, three hundred forty-five million, eight hundred eighty-four thousand, three hundred nine".