12042421 has 2 divisors, whose sum is σ = 12042422. Its totient is φ = 12042420.

The previous prime is 12042419. The next prime is 12042439. The reversal of 12042421 is 12424021.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12040900 + 1521 = 3470^2 + 39^2 .

It is a cyclic number.

It is not a de Polignac number, because 12042421 - 2¹ = 12042419 is a prime.

Together with 12042419, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 12042395 and 12042404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12042461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6021210 + 6021211.

It is an arithmetic number, because the mean of its divisors is an integer number (6021211).

Almost surely, 2^12042421 is an apocalyptic number.

It is an amenable number.

12042421 is a deficient number, since it is larger than the sum of its proper divisors (1).

12042421 is an equidigital number, since it uses as much as digits as its factorization.

12042421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 12042421 is about 3470.2191573444. The cubic root of 12042421 is about 229.2123085877.

Adding to 12042421 its reverse (12424021), we get a palindrome (24466442).

The spelling of 12042421 in words is "twelve million, forty-two thousand, four hundred twenty-one".