21544253324 has 96 divisors (see below), whose sum is σ = 42551308800. Its totient is φ = 9461813760.

The previous prime is 21544253299. The next prime is 21544253327. The reversal of 21544253324 is 42335244512.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21544253327) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 52675232 + ... + 52675640.

It is an arithmetic number, because the mean of its divisors is an integer number (443242800).

Almost surely, 2^21544253324 is an apocalyptic number.

It is an amenable number.

21544253324 is a deficient number, since it is larger than the sum of its proper divisors (21007055476).

21544253324 is a wasteful number, since it uses less digits than its factorization.

21544253324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 783 (or 781 counting only the distinct ones).

The product of its digits is 115200, while the sum is 35.

Adding to 21544253324 its reverse (42335244512), we get a palindrome (63879497836).

The spelling of 21544253324 in words is "twenty-one billion, five hundred forty-four million, two hundred fifty-three thousand, three hundred twenty-four".