21120321100 has 36 divisors (see below), whose sum is σ = 46383296904. Its totient is φ = 8346340480.

The previous prime is 21120321077. The next prime is 21120321149. The reversal of 21120321100 is 112302112.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1264009 + ... + 1280608.

It is an arithmetic number, because the mean of its divisors is an integer number (1288424914).

Almost surely, 2^21120321100 is an apocalyptic number.

21120321100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21120321100 is an abundant number, since it is smaller than the sum of its proper divisors (25262975804).

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

21120321100 is a wasteful number, since it uses less digits than its factorization.

21120321100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2544714 (or 2544707 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21120321100 its reverse (112302112), we get a palindrome (21232623212).

The spelling of 21120321100 in words is "twenty-one billion, one hundred twenty million, three hundred twenty-one thousand, one hundred".