21131211053 has 2 divisors, whose sum is σ = 21131211054. Its totient is φ = 21131211052.

The previous prime is 21131211047. The next prime is 21131211071. The reversal of 21131211053 is 35011213112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21128657449 + 2553604 = 145357^2 + 1598^2 .

It is a cyclic number.

It is not a de Polignac number, because 21131211053 - 2¹⁰ = 21131210029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21131211553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10565605526 + 10565605527.

It is an arithmetic number, because the mean of its divisors is an integer number (10565605527).

Almost surely, 2^21131211053 is an apocalyptic number.

It is an amenable number.

21131211053 is a deficient number, since it is larger than the sum of its proper divisors (1).

21131211053 is an equidigital number, since it uses as much as digits as its factorization.

21131211053 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 180, while the sum is 20.

Adding to 21131211053 its reverse (35011213112), we get a palindrome (56142424165).

The spelling of 21131211053 in words is "twenty-one billion, one hundred thirty-one million, two hundred eleven thousand, fifty-three".