20746006409 has 4 divisors (see below), whose sum is σ = 20751888660. Its totient is φ = 20740124160.

The previous prime is 20746006397. The next prime is 20746006427. The reversal of 20746006409 is 90460064702.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1404150784 + 19341855625 = 37472^2 + 139075^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20746006409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20746006499) 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 in 3 ways as a sum of consecutive naturals, for example, 2935832 + ... + 2942889.

It is an arithmetic number, because the mean of its divisors is an integer number (5187972165).

Almost surely, 2^20746006409 is an apocalyptic number.

It is an amenable number.

20746006409 is a deficient number, since it is larger than the sum of its proper divisors (5882251).

20746006409 is an equidigital number, since it uses as much as digits as its factorization.

20746006409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5882250.

The product of its (nonzero) digits is 72576, while the sum is 38.

The spelling of 20746006409 in words is "twenty billion, seven hundred forty-six million, six thousand, four hundred nine".