21222423055 has 4 divisors (see below), whose sum is σ = 25466907672. Its totient is φ = 16977938440.

The previous prime is 21222423049. The next prime is 21222423071. The reversal of 21222423055 is 55032422212.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21222423055 - 2⁵ = 21222423023 is a prime.

It is a Duffinian number.

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 3 ways as a sum of consecutive naturals, for example, 2122242301 + ... + 2122242310.

It is an arithmetic number, because the mean of its divisors is an integer number (6366726918).

Almost surely, 2^21222423055 is an apocalyptic number.

21222423055 is a deficient number, since it is larger than the sum of its proper divisors (4244484617).

21222423055 is an equidigital number, since it uses as much as digits as its factorization.

21222423055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4244484616.

The product of its (nonzero) digits is 9600, while the sum is 28.

Adding to 21222423055 its reverse (55032422212), we get a palindrome (76254845267).

The spelling of 21222423055 in words is "twenty-one billion, two hundred twenty-two million, four hundred twenty-three thousand, fifty-five".