642343 has 4 divisors (see below), whose sum is σ = 691768. Its totient is φ = 592920.

The previous prime is 642281. The next prime is 642359. The reversal of 642343 is 343246.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642343 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642373) 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 3 ways as a sum of consecutive naturals, for example, 24693 + ... + 24718.

It is an arithmetic number, because the mean of its divisors is an integer number (172942).

2⁶⁴²³⁴³ is an apocalyptic number.

642343 is a deficient number, since it is larger than the sum of its proper divisors (49425).

642343 is a wasteful number, since it uses less digits than its factorization.

642343 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49424.

The product of its digits is 1728, while the sum is 22.

The square root of 642343 is about 801.4630372013. The cubic root of 642343 is about 86.2824228728.

Adding to 642343 its reverse (343246), we get a palindrome (985589).

The spelling of 642343 in words is "six hundred forty-two thousand, three hundred forty-three".