21216351120503 has 8 divisors (see below), whose sum is σ = 26451554643840. Its totient is φ = 16532221652280.

The previous prime is 21216351120493. The next prime is 21216351120521. The reversal of 21216351120503 is 30502115361212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21216351120503 - 2¹⁶ = 21216351054967 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 21216351120503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21216351122503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 137768513693 + ... + 137768513846.

It is an arithmetic number, because the mean of its divisors is an integer number (3306444330480).

Almost surely, 2^{21216351120503} is an apocalyptic number.

21216351120503 is a deficient number, since it is larger than the sum of its proper divisors (5235203523337).

21216351120503 is a wasteful number, since it uses less digits than its factorization.

21216351120503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275537027557.

The product of its (nonzero) digits is 10800, while the sum is 32.

Adding to 21216351120503 its reverse (30502115361212), we get a palindrome (51718466481715).

The spelling of 21216351120503 in words is "twenty-one trillion, two hundred sixteen billion, three hundred fifty-one million, one hundred twenty thousand, five hundred three".