21000105135 has 48 divisors (see below), whose sum is σ = 37282982880. Its totient is φ = 10931500800.

The previous prime is 21000105101. The next prime is 21000105149. The reversal of 21000105135 is 53150100012.

It is not a de Polignac number, because 21000105135 - 2⁹ = 21000104623 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 296685 + ... + 360585.

It is an arithmetic number, because the mean of its divisors is an integer number (776728810).

Almost surely, 2^21000105135 is an apocalyptic number.

21000105135 is a deficient number, since it is larger than the sum of its proper divisors (16282877745).

21000105135 is a wasteful number, since it uses less digits than its factorization.

21000105135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64088 (or 64085 counting only the distinct ones).

The product of its (nonzero) digits is 150, while the sum is 18.

Adding to 21000105135 its reverse (53150100012), we get a palindrome (74150205147).

The spelling of 21000105135 in words is "twenty-one billion, one hundred five thousand, one hundred thirty-five".