21227126221 has 8 divisors (see below), whose sum is σ = 24261917760. Its totient is φ = 18192920928.

The previous prime is 21227126197. The next prime is 21227126231. The reversal of 21227126221 is 12262172212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21227126221 - 2⁵ = 21227126189 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21227126221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21227126231) 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, 66016 + ... + 216361.

It is an arithmetic number, because the mean of its divisors is an integer number (3032739720).

Almost surely, 2^21227126221 is an apocalyptic number.

It is an amenable number.

21227126221 is a deficient number, since it is larger than the sum of its proper divisors (3034791539).

21227126221 is a wasteful number, since it uses less digits than its factorization.

21227126221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293123.

The product of its digits is 2688, while the sum is 28.

Adding to 21227126221 its reverse (12262172212), we get a palindrome (33489298433).

The spelling of 21227126221 in words is "twenty-one billion, two hundred twenty-seven million, one hundred twenty-six thousand, two hundred twenty-one".