21313213333 has 2 divisors, whose sum is σ = 21313213334. Its totient is φ = 21313213332.

The previous prime is 21313213331. The next prime is 21313213343. The reversal of 21313213333 is 33331231312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19831117329 + 1482096004 = 140823^2 + 38498^2 .

It is a cyclic number.

It is not a de Polignac number, because 21313213333 - 2¹ = 21313213331 is a prime.

Together with 21313213331, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 21313213298 and 21313213307.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21313213331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10656606666 + 10656606667.

It is an arithmetic number, because the mean of its divisors is an integer number (10656606667).

Almost surely, 2^21313213333 is an apocalyptic number.

It is an amenable number.

21313213333 is a deficient number, since it is larger than the sum of its proper divisors (1).

21313213333 is an equidigital number, since it uses as much as digits as its factorization.

21313213333 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2916, while the sum is 25.

Adding to 21313213333 its reverse (33331231312), we get a palindrome (54644444645).

The spelling of 21313213333 in words is "twenty-one billion, three hundred thirteen million, two hundred thirteen thousand, three hundred thirty-three".