642388242 has 16 divisors (see below), whose sum is σ = 1285026912. Its totient is φ = 214087680.

The previous prime is 642388213. The next prime is 642388259. The reversal of 642388242 is 242883246.

It is a self number, because there is not a number n which added to its sum of digits gives 642388242.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48658 + ... + 60434.

It is an arithmetic number, because the mean of its divisors is an integer number (80314182).

Almost surely, 2^642388242 is an apocalyptic number.

642388242 is an abundant number, since it is smaller than the sum of its proper divisors (642638670).

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

642388242 is a wasteful number, since it uses less digits than its factorization.

642388242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20873.

The product of its digits is 147456, while the sum is 39.

The square root of 642388242 is about 25345.3791054701. The cubic root of 642388242 is about 862.8444852875.

The spelling of 642388242 in words is "six hundred forty-two million, three hundred eighty-eight thousand, two hundred forty-two".