640194 has 8 divisors (see below), whose sum is σ = 1280400. Its totient is φ = 213396.

The previous prime is 640193. The next prime is 640219. The reversal of 640194 is 491046.

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

640194 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (640193) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53344 + ... + 53355.

It is an arithmetic number, because the mean of its divisors is an integer number (160050).

2⁶⁴⁰¹⁹⁴ is an apocalyptic number.

640194 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.

640194 is a wasteful number, since it uses less digits than its factorization.

640194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106704.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 640194 is about 800.1212408129. The cubic root of 640194 is about 86.1860942285.

The spelling of 640194 in words is "six hundred forty thousand, one hundred ninety-four".