642117438 has 24 divisors (see below), whose sum is σ = 1473093648. Its totient is φ = 201448512.

The previous prime is 642117433. The next prime is 642117491. The reversal of 642117438 is 834711246.

642117438 is a `hidden beast` number, since 6 + 4 + 211 + 7 + 438 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642117433) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1048906 + ... + 1049517.

It is an arithmetic number, because the mean of its divisors is an integer number (61378902).

Almost surely, 2^642117438 is an apocalyptic number.

642117438 is an abundant number, since it is smaller than the sum of its proper divisors (830976210).

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

642117438 is a wasteful number, since it uses less digits than its factorization.

642117438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2098448 (or 2098445 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 642117438 is about 25340.0362667459. The cubic root of 642117438 is about 862.7232218706.

The spelling of 642117438 in words is "six hundred forty-two million, one hundred seventeen thousand, four hundred thirty-eight".