20623610309 has 2 divisors, whose sum is σ = 20623610310. Its totient is φ = 20623610308.

The previous prime is 20623610297. The next prime is 20623610323. The reversal of 20623610309 is 90301632602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14569214209 + 6054396100 = 120703^2 + 77810^2 .

It is a cyclic number.

It is not a de Polignac number, because 20623610309 - 2²⁰ = 20622561733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20623610369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10311805154 + 10311805155.

It is an arithmetic number, because the mean of its divisors is an integer number (10311805155).

Almost surely, 2^20623610309 is an apocalyptic number.

It is an amenable number.

20623610309 is a deficient number, since it is larger than the sum of its proper divisors (1).

20623610309 is an equidigital number, since it uses as much as digits as its factorization.

20623610309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11664, while the sum is 32.

The spelling of 20623610309 in words is "twenty billion, six hundred twenty-three million, six hundred ten thousand, three hundred nine".