21102112220 has 48 divisors (see below), whose sum is σ = 52847036928. Its totient is φ = 6920443200.

The previous prime is 21102112219. The next prime is 21102112231. The reversal of 21102112220 is 2221120112.

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

It is a junction number, because it is equal to n+sod(n) for n = 21102112195 and 21102112204.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 3273506 + ... + 3279945.

It is an arithmetic number, because the mean of its divisors is an integer number (1100979936).

Almost surely, 2^21102112220 is an apocalyptic number.

21102112220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21102112220 is an abundant number, since it is smaller than the sum of its proper divisors (31744924708).

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

21102112220 is a wasteful number, since it uses less digits than its factorization.

21102112220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6553490 (or 6553488 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21102112220 its reverse (2221120112), we get a palindrome (23323232332).

The spelling of 21102112220 in words is "twenty-one billion, one hundred two million, one hundred twelve thousand, two hundred twenty".