7938840 has 128 divisors (see below), whose sum is σ = 29352960. Its totient is φ = 1672704.

The previous prime is 7938839. The next prime is 7938851. The reversal of 7938840 is 488397.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10557 + ... + 11283.

It is an arithmetic number, because the mean of its divisors is an integer number (229320).

Almost surely, 2^7938840 is an apocalyptic number.

7938840 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7938840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14676480).

7938840 is an abundant number, since it is smaller than the sum of its proper divisors (21414120).

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

7938840 is a wasteful number, since it uses less digits than its factorization.

7938840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 761 (or 757 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 39.

The square root of 7938840 is about 2817.5947189048. The cubic root of 7938840 is about 199.4890289882.

It can be divided in two parts, 7938 and 840, that added together give a palindrome (8778).

The spelling of 7938840 in words is "seven million, nine hundred thirty-eight thousand, eight hundred forty".