306138 has 32 divisors (see below), whose sum is σ = 722304. Its totient is φ = 84672.

The previous prime is 306133. The next prime is 306139. The reversal of 306138 is 831603.

306138 = T₁₁₂ + T₁₁₃ + ... + T₁₄₇.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 306138.

It is not an unprimeable number, because it can be changed into a prime (306133) 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 15 ways as a sum of consecutive naturals, for example, 1456 + ... + 1652.

It is an arithmetic number, because the mean of its divisors is an integer number (22572).

2³⁰⁶¹³⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 306138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (361152).

306138 is an abundant number, since it is smaller than the sum of its proper divisors (416166).

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

306138 is a wasteful number, since it uses less digits than its factorization.

306138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 306138 is about 553.2973883907. The cubic root of 306138 is about 67.3967695036.

It can be divided in two parts, 306 and 138, that added together give a palindrome (444).

The spelling of 306138 in words is "three hundred six thousand, one hundred thirty-eight".