21000000000222 has 40 divisors (see below), whose sum is σ = 47197717475832. Its totient is φ = 6978851946000.

The previous prime is 21000000000179. The next prime is 21000000000229. The reversal of 21000000000222 is 22200000000012.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000000000229) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 195761529 + ... + 195868772.

Almost surely, 2^{21000000000222} is an apocalyptic number.

21000000000222 is an abundant number, since it is smaller than the sum of its proper divisors (26197717475610).

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

21000000000222 is a wasteful number, since it uses less digits than its factorization.

21000000000222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391630646 (or 391630637 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

Adding to 21000000000222 its reverse (22200000000012), we get a palindrome (43200000000234).

The spelling of 21000000000222 in words is "twenty-one trillion, two hundred twenty-two", and thus it is an aban number.