21616210004521 has 8 divisors (see below), whose sum is σ = 23594864724288. Its totient is φ = 19639812738000.

The previous prime is 21616210004453. The next prime is 21616210004561. The reversal of 21616210004521 is 12540001261612.

It is a happy number.

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 21616210004521 - 2⁷ = 21616210004393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21616210004561) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 564343285 + ... + 564381586.

It is an arithmetic number, because the mean of its divisors is an integer number (2949358090536).

Almost surely, 2^{21616210004521} is an apocalyptic number.

It is an amenable number.

21616210004521 is a deficient number, since it is larger than the sum of its proper divisors (1978654719767).

21616210004521 is a wasteful number, since it uses less digits than its factorization.

21616210004521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1128726623.

The product of its (nonzero) digits is 5760, while the sum is 31.

The spelling of 21616210004521 in words is "twenty-one trillion, six hundred sixteen billion, two hundred ten million, four thousand, five hundred twenty-one".