21222222222 has 16 divisors (see below), whose sum is σ = 44289855360. Its totient is φ = 6766505592.

The previous prime is 21222222209. The next prime is 21222222223. The reversal of 21222222222 is 22222222212.

It is a nude number because it is divisible by every one of its digits.

21222222222 is a modest number, since divided by 222222 gives 21222 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222222223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76891972 + ... + 76892247.

It is an arithmetic number, because the mean of its divisors is an integer number (2768115960).

Almost surely, 2^21222222222 is an apocalyptic number.

21222222222 is an abundant number, since it is smaller than the sum of its proper divisors (23067633138).

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

21222222222 is a wasteful number, since it uses less digits than its factorization.

21222222222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153784247.

The product of its digits is 1024, while the sum is 21.

Adding to 21222222222 its reverse (22222222212), we get a palindrome (43444444434).

The spelling of 21222222222 in words is "twenty-one billion, two hundred twenty-two million, two hundred twenty-two thousand, two hundred twenty-two".