21344422221 has 48 divisors (see below), whose sum is σ = 32074518528. Its totient is φ = 13667961600.

The previous prime is 21344422207. The next prime is 21344422273. The reversal of 21344422221 is 12222444312.

It is a happy number.

21344422221 is a `hidden beast` number, since 2 + 13 + 4 + 4 + 422 + 221 = 666.

It is not a de Polignac number, because 21344422221 - 2¹⁵ = 21344389453 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21344426221) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 19635540 + ... + 19636626.

It is an arithmetic number, because the mean of its divisors is an integer number (668219136).

Almost surely, 2^21344422221 is an apocalyptic number.

It is an amenable number.

21344422221 is a deficient number, since it is larger than the sum of its proper divisors (10730096307).

21344422221 is a wasteful number, since it uses less digits than its factorization.

21344422221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1962 (or 1959 counting only the distinct ones).

The product of its digits is 6144, while the sum is 27.

Adding to 21344422221 its reverse (12222444312), we get a palindrome (33566866533).

The spelling of 21344422221 in words is "twenty-one billion, three hundred forty-four million, four hundred twenty-two thousand, two hundred twenty-one".