7818642 has 24 divisors (see below), whose sum is σ = 18244044. Its totient is φ = 2405664.

The previous prime is 7818637. The next prime is 7818649. The reversal of 7818642 is 2468187.

7818642 is a `hidden beast` number, since 7 + 8 + 1 + 8 + 642 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 7733961 + 84681 = 2781^2 + 291^2 .

It is a super-2 number, since 2×7818642² = 122262325448328, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7818597 and 7818606.

It is not an unprimeable number, because it can be changed into a prime (7818649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16473 + ... + 16940.

Almost surely, 2^7818642 is an apocalyptic number.

7818642 is an abundant number, since it is smaller than the sum of its proper divisors (10425402).

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

7818642 is a wasteful number, since it uses less digits than its factorization.

7818642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33434 (or 33431 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

The square root of 7818642 is about 2796.1834703753. The cubic root of 7818642 is about 198.4771169006.

The spelling of 7818642 in words is "seven million, eight hundred eighteen thousand, six hundred forty-two".