21221352511403 has 48 divisors (see below), whose sum is σ = 23794917302016. Its totient is φ = 18765759600000.

The previous prime is 21221352511391. The next prime is 21221352511417. The reversal of 21221352511403 is 30411525312212.

It is not a de Polignac number, because 21221352511403 - 2³⁰ = 21220278769579 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 21221352511403.

It is not an unprimeable number, because it can be changed into a prime (21221352511433) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2334320888 + ... + 2334329978.

It is an arithmetic number, because the mean of its divisors is an integer number (495727443792).

Almost surely, 2^{21221352511403} is an apocalyptic number.

21221352511403 is a deficient number, since it is larger than the sum of its proper divisors (2573564790613).

21221352511403 is a wasteful number, since it uses less digits than its factorization.

21221352511403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9668 (or 9567 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 32.

Adding to 21221352511403 its reverse (30411525312212), we get a palindrome (51632877823615).

The spelling of 21221352511403 in words is "twenty-one trillion, two hundred twenty-one billion, three hundred fifty-two million, five hundred eleven thousand, four hundred three".