21121322213 has 8 divisors (see below), whose sum is σ = 21422755800. Its totient is φ = 20820215808.

The previous prime is 21121322207. The next prime is 21121322219. The reversal of 21121322213 is 31222312112.

It is an interprime number because it is at equal distance from previous prime (21121322207) and next prime (21121322219).

It can be written as a sum of positive squares in 4 ways, for example, as 9560341729 + 11560980484 = 97777^2 + 107522^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21121322213 - 2⁴ = 21121322197 is a prime.

It is a super-2 number, since 2×21121322213² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121322219) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49733 + ... + 211461.

It is an arithmetic number, because the mean of its divisors is an integer number (2677844475).

Almost surely, 2^21121322213 is an apocalyptic number.

It is an amenable number.

21121322213 is a deficient number, since it is larger than the sum of its proper divisors (301433587).

21121322213 is a wasteful number, since it uses less digits than its factorization.

21121322213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163591.

The product of its digits is 288, while the sum is 20.

Adding to 21121322213 its reverse (31222312112), we get a palindrome (52343634325).

The spelling of 21121322213 in words is "twenty-one billion, one hundred twenty-one million, three hundred twenty-two thousand, two hundred thirteen".