21247313603 has 16 divisors (see below), whose sum is σ = 22542130176. Its totient is φ = 19991409120.

The previous prime is 21247313599. The next prime is 21247313621. The reversal of 21247313603 is 30631374212.

It is a cyclic number.

It is not a de Polignac number, because 21247313603 - 2² = 21247313599 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21247313603.

It is not an unprimeable number, because it can be changed into a prime (21247313693) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1740800 + ... + 1752962.

It is an arithmetic number, because the mean of its divisors is an integer number (1408883136).

Almost surely, 2^21247313603 is an apocalyptic number.

21247313603 is a deficient number, since it is larger than the sum of its proper divisors (1294816573).

21247313603 is a wasteful number, since it uses less digits than its factorization.

21247313603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13754.

The product of its (nonzero) digits is 18144, while the sum is 32.

Adding to 21247313603 its reverse (30631374212), we get a palindrome (51878687815).

The spelling of 21247313603 in words is "twenty-one billion, two hundred forty-seven million, three hundred thirteen thousand, six hundred three".