21113442553 has 8 divisors (see below), whose sum is σ = 25549039872. Its totient is φ = 17032693056.

The previous prime is 21113442541. The next prime is 21113442643. The reversal of 21113442553 is 35524431112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21113442553 - 2¹⁷ = 21113311481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21113442653) 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 7 ways as a sum of consecutive naturals, for example, 88711825 + ... + 88712062.

It is an arithmetic number, because the mean of its divisors is an integer number (3193629984).

Almost surely, 2^21113442553 is an apocalyptic number.

It is an amenable number.

21113442553 is a deficient number, since it is larger than the sum of its proper divisors (4435597319).

21113442553 is a wasteful number, since it uses less digits than its factorization.

21113442553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177423911.

The product of its digits is 14400, while the sum is 31.

Adding to 21113442553 its reverse (35524431112), we get a palindrome (56637873665).

The spelling of 21113442553 in words is "twenty-one billion, one hundred thirteen million, four hundred forty-two thousand, five hundred fifty-three".