21125336100 has 288 divisors, whose sum is σ = 68744350080. Its totient is φ = 4964352000.

The previous prime is 21125336081. The next prime is 21125336123. The reversal of 21125336100 is 163352112.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 26112496 + ... + 26113304.

It is an arithmetic number, because the mean of its divisors is an integer number (238695660).

Almost surely, 2^21125336100 is an apocalyptic number.

21125336100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21125336100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34372175040).

21125336100 is an abundant number, since it is smaller than the sum of its proper divisors (47619013980).

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

21125336100 is a wasteful number, since it uses less digits than its factorization.

21125336100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1071 (or 1064 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 24.

Adding to 21125336100 its reverse (163352112), we get a palindrome (21288688212).

The spelling of 21125336100 in words is "twenty-one billion, one hundred twenty-five million, three hundred thirty-six thousand, one hundred".