21153143553 has 8 divisors (see below), whose sum is σ = 28860103008. Its totient is φ = 13774139904.

The previous prime is 21153143549. The next prime is 21153143567. The reversal of 21153143553 is 35534135112.

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

It is not a de Polignac number, because 21153143553 - 2² = 21153143549 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21153123553) 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 in 7 ways as a sum of consecutive naturals, for example, 81988800 + ... + 81989057.

It is an arithmetic number, because the mean of its divisors is an integer number (3607512876).

Almost surely, 2^21153143553 is an apocalyptic number.

It is an amenable number.

21153143553 is a deficient number, since it is larger than the sum of its proper divisors (7706959455).

21153143553 is a wasteful number, since it uses less digits than its factorization.

21153143553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163977903.

The product of its digits is 27000, while the sum is 33.

Adding to 21153143553 its reverse (35534135112), we get a palindrome (56687278665).

The spelling of 21153143553 in words is "twenty-one billion, one hundred fifty-three million, one hundred forty-three thousand, five hundred fifty-three".