7278840 has 48 divisors (see below), whose sum is σ = 23657400. Its totient is φ = 1940928.

The previous prime is 7278829. The next prime is 7278841. The reversal of 7278840 is 488727.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 7278795 and 7278804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7278841) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9750 + ... + 10469.

Almost surely, 2^7278840 is an apocalyptic number.

It is an amenable number.

7278840 is an abundant number, since it is smaller than the sum of its proper divisors (16378560).

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

7278840 is a wasteful number, since it uses less digits than its factorization.

7278840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20236 (or 20229 counting only the distinct ones).

The product of its (nonzero) digits is 25088, while the sum is 36.

The square root of 7278840 is about 2697.9325417808. The cubic root of 7278840 is about 193.8001271617.

It can be divided in two parts, 7278 and 840, that added together give a palindrome (8118).

The spelling of 7278840 in words is "seven million, two hundred seventy-eight thousand, eight hundred forty".