21012102122213 has 6 divisors (see below), whose sum is σ = 22320814365426. Its totient is φ = 19776096114752.

The previous prime is 21012102122173. The next prime is 21012102122279. The reversal of 21012102122213 is 31222120121012.

It can be written as a sum of positive squares in 3 ways, for example, as 7719828857764 + 13292273264449 = 2778458^2 + 3645857^2 .

It is not a de Polignac number, because 21012102122213 - 2⁶ = 21012102122149 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 (21012102124213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36353117570 + ... + 36353118147.

It is an arithmetic number, because the mean of its divisors is an integer number (3720135727571).

Almost surely, 2^{21012102122213} is an apocalyptic number.

It is an amenable number.

21012102122213 is a deficient number, since it is larger than the sum of its proper divisors (1308712243213).

21012102122213 is an equidigital number, since it uses as much as digits as its factorization.

21012102122213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72706235751 (or 72706235734 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 21012102122213 its reverse (31222120121012), we get a palindrome (52234222243225).

The spelling of 21012102122213 in words is "twenty-one trillion, twelve billion, one hundred two million, one hundred twenty-two thousand, two hundred thirteen".