21153324252 has 24 divisors (see below), whose sum is σ = 49437770256. Its totient is φ = 7039677568.

The previous prime is 21153324223. The next prime is 21153324259. The reversal of 21153324252 is 25242335112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21153324259) 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, 1421103 + ... + 1435910.

It is an arithmetic number, because the mean of its divisors is an integer number (2059907094).

Almost surely, 2^21153324252 is an apocalyptic number.

It is an amenable number.

21153324252 is an abundant number, since it is smaller than the sum of its proper divisors (28284446004).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21153324252 is a wasteful number, since it uses less digits than its factorization.

21153324252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2857637 (or 2857635 counting only the distinct ones).

The product of its digits is 14400, while the sum is 30.

Adding to 21153324252 its reverse (25242335112), we get a palindrome (46395659364).

The spelling of 21153324252 in words is "twenty-one billion, one hundred fifty-three million, three hundred twenty-four thousand, two hundred fifty-two".