21220011100 has 18 divisors (see below), whose sum is σ = 46047424304. Its totient is φ = 8488004400.

The previous prime is 21220011089. The next prime is 21220011101. The reversal of 21220011100 is 111002212.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220011101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 106099956 + ... + 106100155.

Almost surely, 2^21220011100 is an apocalyptic number.

21220011100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21220011100 is an abundant number, since it is smaller than the sum of its proper divisors (24827413204).

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

21220011100 is a wasteful number, since it uses less digits than its factorization.

21220011100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212200125 (or 212200118 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21220011100 its reverse (111002212), we get a palindrome (21331013312).

The spelling of 21220011100 in words is "twenty-one billion, two hundred twenty million, eleven thousand, one hundred".