640270 has 16 divisors (see below), whose sum is σ = 1180080. Its totient is φ = 249984.

The previous prime is 640267. The next prime is 640279. The reversal of 640270 is 72046.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640279) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 315 + ... + 1174.

It is an arithmetic number, because the mean of its divisors is an integer number (73755).

2⁶⁴⁰²⁷⁰ is an apocalyptic number.

640270 is a deficient number, since it is larger than the sum of its proper divisors (539810).

640270 is a wasteful number, since it uses less digits than its factorization.

640270 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1539.

The product of its (nonzero) digits is 336, while the sum is 19.

The square root of 640270 is about 800.1687322059. The cubic root of 640270 is about 86.1895045926.

The spelling of 640270 in words is "six hundred forty thousand, two hundred seventy".