20205711 has 12 divisors (see below), whose sum is σ = 29259360. Its totient is φ = 13436640.

The previous prime is 20205709. The next prime is 20205727. The reversal of 20205711 is 11750202.

It is not a de Polignac number, because 20205711 - 2¹ = 20205709 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20205781) 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 in 11 ways as a sum of consecutive naturals, for example, 1275 + ... + 6483.

It is an arithmetic number, because the mean of its divisors is an integer number (2438280).

Almost surely, 2^20205711 is an apocalyptic number.

20205711 is a deficient number, since it is larger than the sum of its proper divisors (9053649).

20205711 is a wasteful number, since it uses less digits than its factorization.

20205711 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5646 (or 5643 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 18.

The square root of 20205711 is about 4495.0763063601. The cubic root of 20205711 is about 272.3692316480.

Adding to 20205711 its reverse (11750202), we get a palindrome (31955913).

The spelling of 20205711 in words is "twenty million, two hundred five thousand, seven hundred eleven".