21833505217 has 2 divisors, whose sum is σ = 21833505218. Its totient is φ = 21833505216.

The previous prime is 21833505179. The next prime is 21833505241. The reversal of 21833505217 is 71250533812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16994772496 + 4838732721 = 130364^2 + 69561^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21833505217 is a prime.

It is not a weakly prime, because it can be changed into another prime (21833505247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10916752608 + 10916752609.

It is an arithmetic number, because the mean of its divisors is an integer number (10916752609).

Almost surely, 2^21833505217 is an apocalyptic number.

It is an amenable number.

21833505217 is a deficient number, since it is larger than the sum of its proper divisors (1).

21833505217 is an equidigital number, since it uses as much as digits as its factorization.

21833505217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 50400, while the sum is 37.

The spelling of 21833505217 in words is "twenty-one billion, eight hundred thirty-three million, five hundred five thousand, two hundred seventeen".