21243102100 has 36 divisors (see below), whose sum is σ = 50288218848. Its totient is φ = 7724764000.

The previous prime is 21243101983. The next prime is 21243102107. The reversal of 21243102100 is 120134212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21243102107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9654856 + ... + 9657055.

It is an arithmetic number, because the mean of its divisors is an integer number (1396894968).

Almost surely, 2^21243102100 is an apocalyptic number.

21243102100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21243102100 is an abundant number, since it is smaller than the sum of its proper divisors (29045116748).

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

21243102100 is a wasteful number, since it uses less digits than its factorization.

21243102100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19311936 (or 19311929 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21243102100 its reverse (120134212), we get a palindrome (21363236312).

The spelling of 21243102100 in words is "twenty-one billion, two hundred forty-three million, one hundred two thousand, one hundred".