21104455100 has 18 divisors (see below), whose sum is σ = 45796667784. Its totient is φ = 8441782000.

The previous prime is 21104455093. The next prime is 21104455103. The reversal of 21104455100 is 155440112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21104455103) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 105522176 + ... + 105522375.

Almost surely, 2^21104455100 is an apocalyptic number.

21104455100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21104455100 is an abundant number, since it is smaller than the sum of its proper divisors (24692212684).

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

21104455100 is a wasteful number, since it uses less digits than its factorization.

21104455100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211044565 (or 211044558 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 23.

Adding to 21104455100 its reverse (155440112), we get a palindrome (21259895212).

The spelling of 21104455100 in words is "twenty-one billion, one hundred four million, four hundred fifty-five thousand, one hundred".