21312234505189 has 2 divisors, whose sum is σ = 21312234505190. Its totient is φ = 21312234505188.

The previous prime is 21312234505187. The next prime is 21312234505283. The reversal of 21312234505189 is 98150543221312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15937325496964 + 5374909008225 = 3992158^2 + 2318385^2 .

It is a cyclic number.

It is not a de Polignac number, because 21312234505189 - 2¹ = 21312234505187 is a prime.

It is a super-3 number, since 3×21312234505189³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

Together with 21312234505187, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21312234505187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10656117252594 + 10656117252595.

It is an arithmetic number, because the mean of its divisors is an integer number (10656117252595).

Almost surely, 2^{21312234505189} is an apocalyptic number.

It is an amenable number.

21312234505189 is a deficient number, since it is larger than the sum of its proper divisors (1).

21312234505189 is an equidigital number, since it uses as much as digits as its factorization.

21312234505189 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 518400, while the sum is 46.

The spelling of 21312234505189 in words is "twenty-one trillion, three hundred twelve billion, two hundred thirty-four million, five hundred five thousand, one hundred eighty-nine".