7278428 has 24 divisors (see below), whose sum is σ = 13332480. Its totient is φ = 3472560.

The previous prime is 7278421. The next prime is 7278473. The reversal of 7278428 is 8248727.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 7278391 and 7278400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7278421) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9425 + ... + 10167.

It is an arithmetic number, because the mean of its divisors is an integer number (555520).

Almost surely, 2^7278428 is an apocalyptic number.

It is an amenable number.

7278428 is a deficient number, since it is larger than the sum of its proper divisors (6054052).

7278428 is a wasteful number, since it uses less digits than its factorization.

7278428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 857 (or 855 counting only the distinct ones).

The product of its digits is 50176, while the sum is 38.

The square root of 7278428 is about 2697.8561859373. The cubic root of 7278428 is about 193.7964705737.

Subtracting 7278428 from its reverse (8248727), we obtain a cube (970299 = 99³).

The spelling of 7278428 in words is "seven million, two hundred seventy-eight thousand, four hundred twenty-eight".