21022221108 has 48 divisors (see below), whose sum is σ = 56369016704. Its totient is φ = 5973160320.

The previous prime is 21022221107. The next prime is 21022221163. The reversal of 21022221108 is 80112222012.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21022221107) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 676135 + ... + 706542.

Almost surely, 2^21022221108 is an apocalyptic number.

21022221108 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21022221108 is an abundant number, since it is smaller than the sum of its proper divisors (35346795596).

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

21022221108 is a wasteful number, since it uses less digits than its factorization.

21022221108 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1382872 (or 1382870 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 21.

The spelling of 21022221108 in words is "twenty-one billion, twenty-two million, two hundred twenty-one thousand, one hundred eight".