21023221100 has 72 divisors (see below), whose sum is σ = 52156661760. Its totient is φ = 7205325120.

The previous prime is 21023221091. The next prime is 21023221123. The reversal of 21023221100 is 112232012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3580367 + ... + 3586233.

It is an arithmetic number, because the mean of its divisors is an integer number (724398080).

Almost surely, 2^21023221100 is an apocalyptic number.

21023221100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21023221100 is an abundant number, since it is smaller than the sum of its proper divisors (31133440660).

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

21023221100 is a wasteful number, since it uses less digits than its factorization.

21023221100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11007 (or 11000 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21023221100 its reverse (112232012), we get a palindrome (21135453112).

The spelling of 21023221100 in words is "twenty-one billion, twenty-three million, two hundred twenty-one thousand, one hundred".