321138 has 32 divisors (see below), whose sum is σ = 753600. Its totient is φ = 101088.

The previous prime is 321109. The next prime is 321143. The reversal of 321138 is 831123.

321138 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a self number, because there is not a number n which added to its sum of digits gives 321138.

It is an unprimeable number.

321138 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 870 + ... + 1182.

It is an arithmetic number, because the mean of its divisors is an integer number (23550).

2³²¹¹³⁸ is an apocalyptic number.

321138 is a gapful number since it is divisible by the number (38) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 321138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (376800).

321138 is an abundant number, since it is smaller than the sum of its proper divisors (432462).

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

321138 is a wasteful number, since it uses less digits than its factorization.

321138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343 (or 337 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 321138 is about 566.6903916602. The cubic root of 321138 is about 68.4800233008.

It can be divided in two parts, 3211 and 38, that added together give a square (3249 = 57²).

The spelling of 321138 in words is "three hundred twenty-one thousand, one hundred thirty-eight".