7939840 has 36 divisors (see below), whose sum is σ = 19021464. Its totient is φ = 3175424.

The previous prime is 7939837. The next prime is 7939847. The reversal of 7939840 is 489397.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 7939793 and 7939802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7939847) 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, 1822 + ... + 4381.

It is an arithmetic number, because the mean of its divisors is an integer number (528374).

Almost surely, 2^7939840 is an apocalyptic number.

It is an amenable number.

7939840 is an abundant number, since it is smaller than the sum of its proper divisors (11081624).

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

7939840 is an equidigital number, since it uses as much as digits as its factorization.

7939840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6224 (or 6210 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 40.

The square root of 7939840 is about 2817.7721696404. The cubic root of 7939840 is about 199.4974047145.

The spelling of 7939840 in words is "seven million, nine hundred thirty-nine thousand, eight hundred forty".