21216210516360 has 64 divisors (see below), whose sum is σ = 70720701724800. Its totient is φ = 5657656137408.

The previous prime is 21216210516341. The next prime is 21216210516373. The reversal of 21216210516360 is 6361501261212.

21216210516360 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 6 + 2 + 10 + 5 + 1 + 636 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9822318604 + ... + 9822320763.

It is an arithmetic number, because the mean of its divisors is an integer number (1105010964450).

Almost surely, 2^{21216210516360} is an apocalyptic number.

21216210516360 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21216210516360 is an abundant number, since it is smaller than the sum of its proper divisors (49504491208440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21216210516360 is a wasteful number, since it uses less digits than its factorization.

21216210516360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19644639387 (or 19644639377 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

Adding to 21216210516360 its reverse (6361501261212), we get a palindrome (27577711777572).

The spelling of 21216210516360 in words is "twenty-one trillion, two hundred sixteen billion, two hundred ten million, five hundred sixteen thousand, three hundred sixty".