21212310322213 has 4 divisors (see below), whose sum is σ = 21729683744748. Its totient is φ = 20694936899680.

The previous prime is 21212310322169. The next prime is 21212310322337. The reversal of 21212310322213 is 31222301321212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12832171168804 + 8380139153409 = 3582202^2 + 2894847^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212310322213 - 2⁹ = 21212310321701 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212310322013) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 258686711206 + ... + 258686711287.

It is an arithmetic number, because the mean of its divisors is an integer number (5432420936187).

Almost surely, 2^{21212310322213} is an apocalyptic number.

It is an amenable number.

21212310322213 is a deficient number, since it is larger than the sum of its proper divisors (517373422535).

21212310322213 is an equidigital number, since it uses as much as digits as its factorization.

21212310322213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 517373422534.

The product of its (nonzero) digits is 1728, while the sum is 25.

Adding to 21212310322213 its reverse (31222301321212), we get a palindrome (52434611643425).

The spelling of 21212310322213 in words is "twenty-one trillion, two hundred twelve billion, three hundred ten million, three hundred twenty-two thousand, two hundred thirteen".