20336809 has 2 divisors, whose sum is σ = 20336810. Its totient is φ = 20336808.

The previous prime is 20336747. The next prime is 20336839. The reversal of 20336809 is 90863302.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12938409 + 7398400 = 3597^2 + 2720^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20336809 is a prime.

It is equal to p_1290586 and since 20336809 and 1290586 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (20336839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10168404 + 10168405.

It is an arithmetic number, because the mean of its divisors is an integer number (10168405).

Almost surely, 2^20336809 is an apocalyptic number.

It is an amenable number.

20336809 is a deficient number, since it is larger than the sum of its proper divisors (1).

20336809 is an equidigital number, since it uses as much as digits as its factorization.

20336809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 20336809 is about 4509.6351293647. The cubic root of 20336809 is about 272.9570211472.

The spelling of 20336809 in words is "twenty million, three hundred thirty-six thousand, eight hundred nine".