20440420009 has 2 divisors, whose sum is σ = 20440420010. Its totient is φ = 20440420008.

The previous prime is 20440419973. The next prime is 20440420019. The reversal of 20440420009 is 90002404402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19433754025 + 1006665984 = 139405^2 + 31728^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20440420009 is a prime.

It is not a weakly prime, because it can be changed into another prime (20440420019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10220210004 + 10220210005.

It is an arithmetic number, because the mean of its divisors is an integer number (10220210005).

Almost surely, 2^20440420009 is an apocalyptic number.

It is an amenable number.

20440420009 is a deficient number, since it is larger than the sum of its proper divisors (1).

20440420009 is an equidigital number, since it uses as much as digits as its factorization.

20440420009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 25.

The spelling of 20440420009 in words is "twenty billion, four hundred forty million, four hundred twenty thousand, nine".