21035321233 has 2 divisors, whose sum is σ = 21035321234. Its totient is φ = 21035321232.

The previous prime is 21035321221. The next prime is 21035321371. The reversal of 21035321233 is 33212353012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19146810384 + 1888510849 = 138372^2 + 43457^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21035321233 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21035321198 and 21035321207.

It is not a weakly prime, because it can be changed into another prime (21035322233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10517660616 + 10517660617.

It is an arithmetic number, because the mean of its divisors is an integer number (10517660617).

Almost surely, 2^21035321233 is an apocalyptic number.

It is an amenable number.

21035321233 is a deficient number, since it is larger than the sum of its proper divisors (1).

21035321233 is an equidigital number, since it uses as much as digits as its factorization.

21035321233 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3240, while the sum is 25.

Adding to 21035321233 its reverse (33212353012), we get a palindrome (54247674245).

The spelling of 21035321233 in words is "twenty-one billion, thirty-five million, three hundred twenty-one thousand, two hundred thirty-three".