7855138 has 8 divisors (see below), whose sum is σ = 11794860. Its totient is φ = 3923520.

The previous prime is 7855109. The next prime is 7855163. The reversal of 7855138 is 8315587.

It can be written as a sum of positive squares in 2 ways, for example, as 7800849 + 54289 = 2793^2 + 233^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 7855097 and 7855106.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1998 + ... + 4438.

Almost surely, 2^7855138 is an apocalyptic number.

7855138 is a deficient number, since it is larger than the sum of its proper divisors (3939722).

7855138 is a wasteful number, since it uses less digits than its factorization.

7855138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4052.

The product of its digits is 33600, while the sum is 37.

The square root of 7855138 is about 2802.7019106569. The cubic root of 7855138 is about 198.7854560111.

The spelling of 7855138 in words is "seven million, eight hundred fifty-five thousand, one hundred thirty-eight".