642139370 has 16 divisors (see below), whose sum is σ = 1156140000. Its totient is φ = 256791504.

The previous prime is 642139367. The next prime is 642139391. The reversal of 642139370 is 73931246.

It is a self number, because there is not a number n which added to its sum of digits gives 642139370.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 70709 + ... + 79271.

It is an arithmetic number, because the mean of its divisors is an integer number (72258750).

Almost surely, 2^642139370 is an apocalyptic number.

642139370 is a deficient number, since it is larger than the sum of its proper divisors (514000630).

642139370 is a wasteful number, since it uses less digits than its factorization.

642139370 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16069.

The product of its (nonzero) digits is 27216, while the sum is 35.

The square root of 642139370 is about 25340.4690169697. The cubic root of 642139370 is about 862.7330440771.

The spelling of 642139370 in words is "six hundred forty-two million, one hundred thirty-nine thousand, three hundred seventy".