21530052224 has 16 divisors (see below), whose sum is σ = 42891901170. Its totient is φ = 10765026048.

The previous prime is 21530052223. The next prime is 21530052239. The reversal of 21530052224 is 42225003512.

It can be written as a sum of positive squares in only one way, i.e., 12596021824 + 8934030400 = 112232^2 + 94520^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a junction number, because it is equal to n+sod(n) for n = 21530052193 and 21530052202.

It is not an unprimeable number, because it can be changed into a prime (21530052223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84101639 + ... + 84101894.

Almost surely, 2^21530052224 is an apocalyptic number.

It is an amenable number.

21530052224 is a deficient number, since it is larger than the sum of its proper divisors (21361848946).

21530052224 is an equidigital number, since it uses as much as digits as its factorization.

21530052224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168203547 (or 168203535 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 26.

Adding to 21530052224 its reverse (42225003512), we get a palindrome (63755055736).

The spelling of 21530052224 in words is "twenty-one billion, five hundred thirty million, fifty-two thousand, two hundred twenty-four".