7818428 has 6 divisors (see below), whose sum is σ = 13682256. Its totient is φ = 3909212.

The previous prime is 7818397. The next prime is 7818451. The reversal of 7818428 is 8248187.

It is a happy number.

It is a super-2 number, since 2×7818428² = 122255632782368, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7818391 and 7818400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 977300 + ... + 977307.

It is an arithmetic number, because the mean of its divisors is an integer number (2280376).

Almost surely, 2^7818428 is an apocalyptic number.

It is an amenable number.

7818428 is a deficient number, since it is larger than the sum of its proper divisors (5863828).

7818428 is a wasteful number, since it uses less digits than its factorization.

7818428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1954611 (or 1954609 counting only the distinct ones).

The product of its digits is 28672, while the sum is 38.

The square root of 7818428 is about 2796.1452036688. The cubic root of 7818428 is about 198.4753060793.

The spelling of 7818428 in words is "seven million, eight hundred eighteen thousand, four hundred twenty-eight".