21123324113 has 2 divisors, whose sum is σ = 21123324114. Its totient is φ = 21123324112.

The previous prime is 21123324091. The next prime is 21123324133. The reversal of 21123324113 is 31142332112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18123352129 + 2999971984 = 134623^2 + 54772^2 .

It is a cyclic number.

It is not a de Polignac number, because 21123324113 - 2⁶ = 21123324049 is a prime.

It is not a weakly prime, because it can be changed into another prime (21123324133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561662056 + 10561662057.

It is an arithmetic number, because the mean of its divisors is an integer number (10561662057).

Almost surely, 2^21123324113 is an apocalyptic number.

It is an amenable number.

21123324113 is a deficient number, since it is larger than the sum of its proper divisors (1).

21123324113 is an equidigital number, since it uses as much as digits as its factorization.

21123324113 is an evil number, because the sum of its binary digits is even.

The product of its digits is 864, while the sum is 23.

Adding to 21123324113 its reverse (31142332112), we get a palindrome (52265656225).

The spelling of 21123324113 in words is "twenty-one billion, one hundred twenty-three million, three hundred twenty-four thousand, one hundred thirteen".