7240405 has 4 divisors (see below), whose sum is σ = 8688492. Its totient is φ = 5792320.

The previous prime is 7240403. The next prime is 7240411. The reversal of 7240405 is 5040427.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4635409 + 2604996 = 2153^2 + 1614^2 .

It is not a de Polignac number, because 7240405 - 2¹ = 7240403 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7240403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 724036 + ... + 724045.

It is an arithmetic number, because the mean of its divisors is an integer number (2172123).

Almost surely, 2^7240405 is an apocalyptic number.

It is an amenable number.

7240405 is a deficient number, since it is larger than the sum of its proper divisors (1448087).

7240405 is a wasteful number, since it uses less digits than its factorization.

7240405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1448086.

The product of its (nonzero) digits is 1120, while the sum is 22.

The square root of 7240405 is about 2690.8000668946. The cubic root of 7240405 is about 193.4584125873.

Adding to 7240405 its sum of digits (22), we get a palindrome (7240427).

The spelling of 7240405 in words is "seven million, two hundred forty thousand, four hundred five".