21242214424 has 8 divisors (see below), whose sum is σ = 39829152060. Its totient is φ = 10621107208.

The previous prime is 21242214421. The next prime is 21242214457. The reversal of 21242214424 is 42441224212.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

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

It is a junction number, because it is equal to n+sod(n) for n = 21242214392 and 21242214401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21242214421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1327638394 + ... + 1327638409.

Almost surely, 2^21242214424 is an apocalyptic number.

It is an amenable number.

21242214424 is a deficient number, since it is larger than the sum of its proper divisors (18586937636).

21242214424 is a wasteful number, since it uses less digits than its factorization.

21242214424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2655276809 (or 2655276805 counting only the distinct ones).

The product of its digits is 8192, while the sum is 28.

Adding to 21242214424 its reverse (42441224212), we get a palindrome (63683438636).

The spelling of 21242214424 in words is "twenty-one billion, two hundred forty-two million, two hundred fourteen thousand, four hundred twenty-four".