7808138 has 16 divisors (see below), whose sum is σ = 12694920. Its totient is φ = 3601728.

The previous prime is 7808131. The next prime is 7808149. The reversal of 7808138 is 8318087.

It can be written as a sum of positive squares in 4 ways, for example, as 316969 + 7491169 = 563^2 + 2737^2 .

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 7808098 and 7808107.

It is not an unprimeable number, because it can be changed into a prime (7808131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3506 + ... + 5282.

Almost surely, 2^7808138 is an apocalyptic number.

7808138 is a deficient number, since it is larger than the sum of its proper divisors (4886782).

7808138 is a wasteful number, since it uses less digits than its factorization.

7808138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1818 (or 1792 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 35.

The square root of 7808138 is about 2794.3045646457. The cubic root of 7808138 is about 198.3881953228.

The spelling of 7808138 in words is "seven million, eight hundred eight thousand, one hundred thirty-eight".