21123100331100 has 144 divisors (see below), whose sum is σ = 67910932831840. Its totient is φ = 5632488576000.

The previous prime is 21123100331077. The next prime is 21123100331107. The reversal of 21123100331100 is 113300132112.

21123100331100 is a `hidden beast` number, since 2 + 1 + 1 + 231 + 0 + 0 + 331 + 100 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123100331107) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 46464900 + ... + 46917300.

Almost surely, 2^{21123100331100} is an apocalyptic number.

21123100331100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21123100331100 is an abundant number, since it is smaller than the sum of its proper divisors (46787832500740).

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

21123100331100 is a wasteful number, since it uses less digits than its factorization.

21123100331100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 469717 (or 469704 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 21123100331100 its reverse (113300132112), we get a palindrome (21236400463212).

The spelling of 21123100331100 in words is "twenty-one trillion, one hundred twenty-three billion, one hundred million, three hundred thirty-one thousand, one hundred".