21122244421 has 8 divisors (see below), whose sum is σ = 21548606040. Its totient is φ = 20700083712.

The previous prime is 21122244317. The next prime is 21122244443. The reversal of 21122244421 is 12444222112.

It can be written as a sum of positive squares in 4 ways, for example, as 101304225 + 21020940196 = 10065^2 + 144986^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21122244421 - 2²⁷ = 20988026693 is a prime.

It is a super-2 number, since 2×21122244421² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122245421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1040070 + ... + 1060183.

It is an arithmetic number, because the mean of its divisors is an integer number (2693575755).

Almost surely, 2^21122244421 is an apocalyptic number.

It is an amenable number.

21122244421 is a deficient number, since it is larger than the sum of its proper divisors (426361619).

21122244421 is a wasteful number, since it uses less digits than its factorization.

21122244421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2100455.

The product of its digits is 2048, while the sum is 25.

Adding to 21122244421 its reverse (12444222112), we get a palindrome (33566466533).

The spelling of 21122244421 in words is "twenty-one billion, one hundred twenty-two million, two hundred forty-four thousand, four hundred twenty-one".