21042111535 has 16 divisors (see below), whose sum is σ = 25681870656. Its totient is φ = 16548519168.

The previous prime is 21042111527. The next prime is 21042111613. The reversal of 21042111535 is 53511124012.

It is a cyclic number.

It is not a de Polignac number, because 21042111535 - 2³ = 21042111527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 78564 + ... + 219673.

It is an arithmetic number, because the mean of its divisors is an integer number (1605116916).

Almost surely, 2^21042111535 is an apocalyptic number.

21042111535 is a deficient number, since it is larger than the sum of its proper divisors (4639759121).

21042111535 is a wasteful number, since it uses less digits than its factorization.

21042111535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 298482.

The product of its (nonzero) digits is 1200, while the sum is 25.

Adding to 21042111535 its reverse (53511124012), we get a palindrome (74553235547).

The spelling of 21042111535 in words is "twenty-one billion, forty-two million, one hundred eleven thousand, five hundred thirty-five".