640350042 has 8 divisors (see below), whose sum is σ = 1280700096. Its totient is φ = 213450012.

The previous prime is 640350031. The next prime is 640350089. The reversal of 640350042 is 240053046.

It is a sphenic number, since it is the product of 3 distinct primes.

640350042 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 640349994 and 640350021.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53362498 + ... + 53362509.

It is an arithmetic number, because the mean of its divisors is an integer number (160087512).

Almost surely, 2^640350042 is an apocalyptic number.

640350042 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

640350042 is a wasteful number, since it uses less digits than its factorization.

640350042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106725012.

The product of its (nonzero) digits is 2880, while the sum is 24.

The square root of 640350042 is about 25305.1386481086. The cubic root of 640350042 is about 861.9309604251.

The spelling of 640350042 in words is "six hundred forty million, three hundred fifty thousand, forty-two".