21216106512245 has 8 divisors (see below), whose sum is σ = 26799292436640. Its totient is φ = 16079575461840.

The previous prime is 21216106512233. The next prime is 21216106512247. The reversal of 21216106512245 is 54221560161212.

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

It is not a de Polignac number, because 21216106512245 - 2¹⁰ = 21216106511221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21216106512199 and 21216106512208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21216106512247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111663718391 + ... + 111663718580.

It is an arithmetic number, because the mean of its divisors is an integer number (3349911554580).

Almost surely, 2^{21216106512245} is an apocalyptic number.

It is an amenable number.

21216106512245 is a deficient number, since it is larger than the sum of its proper divisors (5583185924395).

21216106512245 is a wasteful number, since it uses less digits than its factorization.

21216106512245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223327436995.

The product of its (nonzero) digits is 57600, while the sum is 38.

Adding to 21216106512245 its reverse (54221560161212), we get a palindrome (75437666673457).

The spelling of 21216106512245 in words is "twenty-one trillion, two hundred sixteen billion, one hundred six million, five hundred twelve thousand, two hundred forty-five".