642642 has 64 divisors (see below), whose sum is σ = 1741824. Its totient is φ = 152640.

The previous prime is 642623. The next prime is 642673. The reversal of 642642 is 246246.

642642 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

642642 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 31 ways as a sum of consecutive naturals, for example, 5953 + ... + 6059.

It is an arithmetic number, because the mean of its divisors is an integer number (27216).

2⁶⁴²⁶⁴² is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642642, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (870912).

642642 is an abundant number, since it is smaller than the sum of its proper divisors (1099182).

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

642642 is a wasteful number, since it uses less digits than its factorization.

642642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143.

The product of its digits is 2304, while the sum is 24.

The square root of 642642 is about 801.6495493668. The cubic root of 642642 is about 86.2958084745.

Adding to 642642 its reverse (246246), we get a palindrome (888888).

The spelling of 642642 in words is "six hundred forty-two thousand, six hundred forty-two".