21021013012313 has 2 divisors, whose sum is σ = 21021013012314. Its totient is φ = 21021013012312.

The previous prime is 21021013012291. The next prime is 21021013012333. The reversal of 21021013012313 is 31321031012012.

It is a happy number.

It is an a-pointer prime, because the next prime (21021013012333) can be obtained adding 21021013012313 to its sum of digits (20).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19732669969609 + 1288343042704 = 4442147^2 + 1135052^2 .

It is a cyclic number.

It is not a de Polignac number, because 21021013012313 - 2¹⁶ = 21021012946777 is a prime.

It is not a weakly prime, because it can be changed into another prime (21021013012333) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510506506156 + 10510506506157.

It is an arithmetic number, because the mean of its divisors is an integer number (10510506506157).

Almost surely, 2^{21021013012313} is an apocalyptic number.

It is an amenable number.

21021013012313 is a deficient number, since it is larger than the sum of its proper divisors (1).

21021013012313 is an equidigital number, since it uses as much as digits as its factorization.

21021013012313 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 20.

Adding to 21021013012313 its reverse (31321031012012), we get a palindrome (52342044024325).

The spelling of 21021013012313 in words is "twenty-one trillion, twenty-one billion, thirteen million, twelve thousand, three hundred thirteen".