21216041265510 has 768 divisors, whose sum is σ = 73325554041600. Its totient is φ = 4323787776000.

The previous prime is 21216041265421. The next prime is 21216041265521. The reversal of 21216041265510 is 1556214061212.

21216041265510 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 60 + 41 + 2 + 6 + 551 + 0 = 666.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 712195696 + ... + 712225484.

It is an arithmetic number, because the mean of its divisors is an integer number (95475981825).

Almost surely, 2^{21216041265510} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21216041265510, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36662777020800).

21216041265510 is an abundant number, since it is smaller than the sum of its proper divisors (52109512776090).

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

21216041265510 is a wasteful number, since it uses less digits than its factorization.

21216041265510 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29974 (or 29961 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The spelling of 21216041265510 in words is "twenty-one trillion, two hundred sixteen billion, forty-one million, two hundred sixty-five thousand, five hundred ten".