21521045324 has 24 divisors (see below), whose sum is σ = 39753898800. Its totient is φ = 10194166368.

The previous prime is 21521045323. The next prime is 21521045333. The reversal of 21521045324 is 42354012512.

It is not an unprimeable number, because it can be changed into a prime (21521045323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 364769 + ... + 419640.

It is an arithmetic number, because the mean of its divisors is an integer number (1656412450).

Almost surely, 2^21521045324 is an apocalyptic number.

It is an amenable number.

21521045324 is a deficient number, since it is larger than the sum of its proper divisors (18232853476).

21521045324 is an equidigital number, since it uses as much as digits as its factorization.

21521045324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 784470 (or 784430 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 29.

Adding to 21521045324 its reverse (42354012512), we get a palindrome (63875057836).

The spelling of 21521045324 in words is "twenty-one billion, five hundred twenty-one million, forty-five thousand, three hundred twenty-four".