20438350109 has 2 divisors, whose sum is σ = 20438350110. Its totient is φ = 20438350108.

The previous prime is 20438350061. The next prime is 20438350139. The reversal of 20438350109 is 90105383402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18954405625 + 1483944484 = 137675^2 + 38522^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20438350109 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20438350139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10219175054 + 10219175055.

It is an arithmetic number, because the mean of its divisors is an integer number (10219175055).

Almost surely, 2^20438350109 is an apocalyptic number.

It is an amenable number.

20438350109 is a deficient number, since it is larger than the sum of its proper divisors (1).

20438350109 is an equidigital number, since it uses as much as digits as its factorization.

20438350109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 35.

The spelling of 20438350109 in words is "twenty billion, four hundred thirty-eight million, three hundred fifty thousand, one hundred nine".