7440421 has 2 divisors, whose sum is σ = 7440422. Its totient is φ = 7440420.

The previous prime is 7440413. The next prime is 7440427. The reversal of 7440421 is 1240447.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6964321 + 476100 = 2639^2 + 690^2 .

It is a cyclic number.

It is not a de Polignac number, because 7440421 - 2³ = 7440413 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 7440392 and 7440401.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7440427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3720210 + 3720211.

It is an arithmetic number, because the mean of its divisors is an integer number (3720211).

Almost surely, 2^7440421 is an apocalyptic number.

It is an amenable number.

7440421 is a deficient number, since it is larger than the sum of its proper divisors (1).

7440421 is an equidigital number, since it uses as much as digits as its factorization.

7440421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 896, while the sum is 22.

The square root of 7440421 is about 2727.7135113498. The cubic root of 7440421 is about 195.2236837053.

Adding to 7440421 its reverse (1240447), we get a palindrome (8680868).

The spelling of 7440421 in words is "seven million, four hundred forty thousand, four hundred twenty-one".