21641104236 has 24 divisors (see below), whose sum is σ = 50498288064. Its totient is φ = 7213361680.

The previous prime is 21641104229. The next prime is 21641104343. The reversal of 21641104236 is 63240114612.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 486571 + ... + 529181.

It is an arithmetic number, because the mean of its divisors is an integer number (2104095336).

Almost surely, 2^21641104236 is an apocalyptic number.

It is an amenable number.

21641104236 is an abundant number, since it is smaller than the sum of its proper divisors (28857183828).

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

21641104236 is a wasteful number, since it uses less digits than its factorization.

21641104236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84941 (or 84939 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

Adding to 21641104236 its reverse (63240114612), we get a palindrome (84881218848).

The spelling of 21641104236 in words is "twenty-one billion, six hundred forty-one million, one hundred four thousand, two hundred thirty-six".