12440424421 has 2 divisors, whose sum is σ = 12440424422. Its totient is φ = 12440424420.

The previous prime is 12440424389. The next prime is 12440424431. The reversal of 12440424421 is 12442404421.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12324108196 + 116316225 = 111014^2 + 10785^2 .

It is a cyclic number.

It is not a de Polignac number, because 12440424421 - 2⁵ = 12440424389 is a prime.

It is a super-2 number, since 2×12440424421² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 12440424421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12440424431) by changing a digit.

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 as a sum of consecutive naturals, namely, 6220212210 + 6220212211.

It is an arithmetic number, because the mean of its divisors is an integer number (6220212211).

Almost surely, 2^12440424421 is an apocalyptic number.

It is an amenable number.

12440424421 is a deficient number, since it is larger than the sum of its proper divisors (1).

12440424421 is an equidigital number, since it uses as much as digits as its factorization.

12440424421 is an odious number, because the sum of its binary digits is odd.

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

Adding to 12440424421 its reverse (12442404421), we get a palindrome (24882828842).

The spelling of 12440424421 in words is "twelve billion, four hundred forty million, four hundred twenty-four thousand, four hundred twenty-one".