20811233 has 2 divisors, whose sum is σ = 20811234. Its totient is φ = 20811232.

The previous prime is 20811229. The next prime is 20811239. The reversal of 20811233 is 33211802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18464209 + 2347024 = 4297^2 + 1532^2 .

It is a cyclic number.

It is not a de Polignac number, because 20811233 - 2² = 20811229 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20811239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10405616 + 10405617.

It is an arithmetic number, because the mean of its divisors is an integer number (10405617).

Almost surely, 2^20811233 is an apocalyptic number.

It is an amenable number.

20811233 is a deficient number, since it is larger than the sum of its proper divisors (1).

20811233 is an equidigital number, since it uses as much as digits as its factorization.

20811233 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 20811233 is about 4561.9330332656. The cubic root of 20811233 is about 275.0632713920.

The spelling of 20811233 in words is "twenty million, eight hundred eleven thousand, two hundred thirty-three".