640272 has 20 divisors (see below), whose sum is σ = 1654160. Its totient is φ = 213408.

The previous prime is 640267. The next prime is 640279. The reversal of 640272 is 272046.

It is a happy number.

640272 is nontrivially palindromic in base 15.

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

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6622 + ... + 6717.

It is an arithmetic number, because the mean of its divisors is an integer number (82708).

2⁶⁴⁰²⁷² is an apocalyptic number.

It is an amenable number.

640272 is an abundant number, since it is smaller than the sum of its proper divisors (1013888).

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

640272 is a wasteful number, since it uses less digits than its factorization.

640272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13350 (or 13344 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 640272 is about 800.1699819413. The cubic root of 640272 is about 86.1895943354.

The spelling of 640272 in words is "six hundred forty thousand, two hundred seventy-two".