7438721 has 2 divisors, whose sum is σ = 7438722. Its totient is φ = 7438720.

The previous prime is 7438693. The next prime is 7438727. The reversal of 7438721 is 1278347.

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., 4752400 + 2686321 = 2180^2 + 1639^2 .

It is a cyclic number.

It is not a de Polignac number, because 7438721 - 2¹⁰ = 7437697 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between odd and even.

It is not a weakly prime, because it can be changed into another prime (7438727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3719360 + 3719361.

It is an arithmetic number, because the mean of its divisors is an integer number (3719361).

Almost surely, 2^7438721 is an apocalyptic number.

It is an amenable number.

7438721 is a deficient number, since it is larger than the sum of its proper divisors (1).

7438721 is an equidigital number, since it uses as much as digits as its factorization.

7438721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9408, while the sum is 32.

The square root of 7438721 is about 2727.4018772451. The cubic root of 7438721 is about 195.2088142268.

The spelling of 7438721 in words is "seven million, four hundred thirty-eight thousand, seven hundred twenty-one".