642043 has 4 divisors (see below), whose sum is σ = 648760. Its totient is φ = 635328.

The previous prime is 642013. The next prime is 642049. The reversal of 642043 is 340246.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 340246 = 2 ⋅170123.

It is a cyclic number.

It is not a de Polignac number, because 642043 - 2⁵ = 642011 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 642043.

It is not an unprimeable number, because it can be changed into a prime (642049) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3213 + ... + 3406.

It is an arithmetic number, because the mean of its divisors is an integer number (162190).

2⁶⁴²⁰⁴³ is an apocalyptic number.

642043 is a deficient number, since it is larger than the sum of its proper divisors (6717).

642043 is an equidigital number, since it uses as much as digits as its factorization.

642043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6716.

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 642043 is about 801.2758576171. The cubic root of 642043 is about 86.2689883279.

Adding to 642043 its reverse (340246), we get a palindrome (982289).

The spelling of 642043 in words is "six hundred forty-two thousand, forty-three".