20136709 has 2 divisors, whose sum is σ = 20136710. Its totient is φ = 20136708.

The previous prime is 20136703. The next prime is 20136731. The reversal of 20136709 is 90763102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18948609 + 1188100 = 4353^2 + 1090^2 .

It is a cyclic number.

It is not a de Polignac number, because 20136709 - 2⁹ = 20136197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20136703) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10068354 + 10068355.

It is an arithmetic number, because the mean of its divisors is an integer number (10068355).

Almost surely, 2^20136709 is an apocalyptic number.

It is an amenable number.

20136709 is a deficient number, since it is larger than the sum of its proper divisors (1).

20136709 is an equidigital number, since it uses as much as digits as its factorization.

20136709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2268, while the sum is 28.

The square root of 20136709 is about 4487.3944555833. The cubic root of 20136709 is about 272.0588333303.

The spelling of 20136709 in words is "twenty million, one hundred thirty-six thousand, seven hundred nine".