21044123100 has 1296 divisors, whose sum is σ = 93360024576. Its totient is φ = 3894912000.

The previous prime is 21044123099. The next prime is 21044123119. The reversal of 21044123100 is 132144012.

21044123100 is a `hidden beast` number, since 210 + 441 + 2 + 3 + 10 + 0 = 666.

It is a super-2 number, since 2×21044123100² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 431 ways as a sum of consecutive naturals, for example, 296396065 + ... + 296396135.

It is an arithmetic number, because the mean of its divisors is an integer number (72037056).

Almost surely, 2^21044123100 is an apocalyptic number.

21044123100 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 21044123100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46680012288).

21044123100 is an abundant number, since it is smaller than the sum of its proper divisors (72315901476).

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

21044123100 is a wasteful number, since it uses less digits than its factorization.

21044123100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21044123100 its reverse (132144012), we get a palindrome (21176267112).

The spelling of 21044123100 in words is "twenty-one billion, forty-four million, one hundred twenty-three thousand, one hundred".