21111065539 has 2 divisors, whose sum is σ = 21111065540. Its totient is φ = 21111065538.

The previous prime is 21111065519. The next prime is 21111065669. The reversal of 21111065539 is 93556011112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21111065539 - 2⁷ = 21111065411 is a prime.

It is not a weakly prime, because it can be changed into another prime (21111065519) 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, 10555532769 + 10555532770.

It is an arithmetic number, because the mean of its divisors is an integer number (10555532770).

Almost surely, 2^21111065539 is an apocalyptic number.

21111065539 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111065539 is an equidigital number, since it uses as much as digits as its factorization.

21111065539 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8100, while the sum is 34.

The spelling of 21111065539 in words is "twenty-one billion, one hundred eleven million, sixty-five thousand, five hundred thirty-nine".