21121032113 has 2 divisors, whose sum is σ = 21121032114. Its totient is φ = 21121032112.

The previous prime is 21121032091. The next prime is 21121032131. The reversal of 21121032113 is 31123012112.

Together with next prime (21121032131) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13822234624 + 7298797489 = 117568^2 + 85433^2 .

It is a cyclic number.

It is not a de Polignac number, because 21121032113 - 2⁸ = 21121031857 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21121032091 and 21121032100.

It is not a weakly prime, because it can be changed into another prime (21121082113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560516056 + 10560516057.

It is an arithmetic number, because the mean of its divisors is an integer number (10560516057).

Almost surely, 2^21121032113 is an apocalyptic number.

It is an amenable number.

21121032113 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121032113 is an equidigital number, since it uses as much as digits as its factorization.

21121032113 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21121032113 its reverse (31123012112), we get a palindrome (52244044225).

The spelling of 21121032113 in words is "twenty-one billion, one hundred twenty-one million, thirty-two thousand, one hundred thirteen".