7840720 has 20 divisors (see below), whose sum is σ = 18229860. Its totient is φ = 3136256.

The previous prime is 7840709. The next prime is 7840727. The reversal of 7840720 is 270487.

It can be written as a sum of positive squares in 2 ways, for example, as 2421136 + 5419584 = 1556^2 + 2328^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×7840720² = 122953780236800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7840727) 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 in 3 ways as a sum of consecutive naturals, for example, 48925 + ... + 49084.

It is an arithmetic number, because the mean of its divisors is an integer number (911493).

Almost surely, 2^7840720 is an apocalyptic number.

It is an amenable number.

7840720 is an abundant number, since it is smaller than the sum of its proper divisors (10389140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7840720 is a wasteful number, since it uses less digits than its factorization.

7840720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98022 (or 98016 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 28.

The square root of 7840720 is about 2800.1285684768. The cubic root of 7840720 is about 198.6637588472.

The spelling of 7840720 in words is "seven million, eight hundred forty thousand, seven hundred twenty".