21233001217 has 2 divisors, whose sum is σ = 21233001218. Its totient is φ = 21233001216.

The previous prime is 21233001191. The next prime is 21233001247. The reversal of 21233001217 is 71210033212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19994242801 + 1238758416 = 141401^2 + 35196^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21233001217 is a prime.

It is a super-2 number, since 2×21233001217² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21233001247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10616500608 + 10616500609.

It is an arithmetic number, because the mean of its divisors is an integer number (10616500609).

Almost surely, 2^21233001217 is an apocalyptic number.

It is an amenable number.

21233001217 is a deficient number, since it is larger than the sum of its proper divisors (1).

21233001217 is an equidigital number, since it uses as much as digits as its factorization.

21233001217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 504, while the sum is 22.

Adding to 21233001217 its reverse (71210033212), we get a palindrome (92443034429).

The spelling of 21233001217 in words is "twenty-one billion, two hundred thirty-three million, one thousand, two hundred seventeen".