342 has 12 divisors (see below), whose sum is σ = 780. Its totient is φ = 108.

The previous prime is 337. The next prime is 347. The reversal of 342 is 243.

342 is nontrivially palindromic in base 5 and base 7.

It is a Cunningham number, because it is equal to 7³-1.

It is an interprime number because it is at equal distance from previous prime (337) and next prime (347).

It is a Harshad number since it is a multiple of its sum of digits (9).

Its product of digits (24) is a multiple of the sum of its prime divisors (24).

342 is a nontrivial repdigit in base 7.

It is a plaindrome in base 4, base 7, base 12, base 15 and base 16.

It is a nialpdrome in base 7 and base 9.

It is a zygodrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (347) by changing a digit.

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

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9 + ... + 27.

It is an arithmetic number, because the mean of its divisors is an integer number (65).

It is a pronic number, being equal to 18×19.

342 is the 12-th heptagonal number.

It is a practical number, because each smaller number is the sum of distinct divisors of 342, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (390).

342 is an abundant number, since it is smaller than the sum of its proper divisors (438).

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

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

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

The sum of its prime factors is 27 (or 24 counting only the distinct ones).

The product of its digits is 24, while the sum is 9.

The square root of 342 is about 18.4932420089. The cubic root of 342 is about 6.9931906572.

Adding to 342 its reverse (243), we get a palindrome (585).

Subtracting from 342 its reverse (243), we obtain a palindrome (99).

It can be divided in two parts, 34 and 2, that added together give a triangular number (36 = T₈).

The spelling of 342 in words is "three hundred forty-two", and thus it is an aban number and an iban number.