642042 has 24 divisors (see below), whose sum is σ = 1419444. Its totient is φ = 209664.

The previous prime is 642013. The next prime is 642049. The reversal of 642042 is 240246.

It can be written as a sum of positive squares in 2 ways, for example, as 641601 + 441 = 801^2 + 21^2 .

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

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

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 618 + ... + 1290.

2⁶⁴²⁰⁴² is an apocalyptic number.

642042 is an abundant number, since it is smaller than the sum of its proper divisors (777402).

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

642042 is a wasteful number, since it uses less digits than its factorization.

642042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 734 (or 731 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 642042 is about 801.2752336120. The cubic root of 642042 is about 86.2689435391.

Adding to 642042 its reverse (240246), we get a palindrome (882288).

It can be divided in two parts, 6 and 42042, that multiplied together give a palindrome (252252).

The spelling of 642042 in words is "six hundred forty-two thousand, forty-two".