21201121100 has 36 divisors (see below), whose sum is σ = 46013466408. Its totient is φ = 8479152000.

The previous prime is 21201121099. The next prime is 21201121111. The reversal of 21201121100 is 112110212.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 897440 + ... + 920760.

Almost surely, 2^21201121100 is an apocalyptic number.

21201121100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201121100 is an abundant number, since it is smaller than the sum of its proper divisors (24812345308).

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

21201121100 is a wasteful number, since it uses less digits than its factorization.

21201121100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32426 (or 32419 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21201121100 its reverse (112110212), we get a palindrome (21313231312).

It can be divided in two parts, 2120112 and 1100, that added together give a palindrome (2121212).

The spelling of 21201121100 in words is "twenty-one billion, two hundred one million, one hundred twenty-one thousand, one hundred".