21353332544 has 14 divisors (see below), whose sum is σ = 42373019394. Its totient is φ = 10676666240.

The previous prime is 21353332489. The next prime is 21353332601. The reversal of 21353332544 is 44523335312.

It can be written as a sum of positive squares in only one way, i.e., 21057492544 + 295840000 = 145112^2 + 17200^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166822847 + ... + 166822974.

Almost surely, 2^21353332544 is an apocalyptic number.

It is an amenable number.

21353332544 is a deficient number, since it is larger than the sum of its proper divisors (21019686850).

21353332544 is an equidigital number, since it uses as much as digits as its factorization.

21353332544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333645833 (or 333645823 counting only the distinct ones).

The product of its digits is 129600, while the sum is 35.

Adding to 21353332544 its reverse (44523335312), we get a palindrome (65876667856).

The spelling of 21353332544 in words is "twenty-one billion, three hundred fifty-three million, three hundred thirty-two thousand, five hundred forty-four".