21113424555 has 16 divisors (see below), whose sum is σ = 33792378144. Its totient is φ = 11256860160.

The previous prime is 21113424551. The next prime is 21113424557. The reversal of 21113424555 is 55542431112.

It is not a de Polignac number, because 21113424555 - 2² = 21113424551 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21113424551) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 178684 + ... + 272313.

It is an arithmetic number, because the mean of its divisors is an integer number (2112023634).

Almost surely, 2^21113424555 is an apocalyptic number.

21113424555 is a deficient number, since it is larger than the sum of its proper divisors (12678953589).

21113424555 is a wasteful number, since it uses less digits than its factorization.

21113424555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 454126.

The product of its digits is 24000, while the sum is 33.

Adding to 21113424555 its reverse (55542431112), we get a palindrome (76655855667).

The spelling of 21113424555 in words is "twenty-one billion, one hundred thirteen million, four hundred twenty-four thousand, five hundred fifty-five".