640180 has 12 divisors (see below), whose sum is σ = 1344420. Its totient is φ = 256064.

The previous prime is 640163. The next prime is 640193. The reversal of 640180 is 81046.

It can be written as a sum of positive squares in 2 ways, for example, as 68644 + 571536 = 262^2 + 756^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15985 + ... + 16024.

It is an arithmetic number, because the mean of its divisors is an integer number (112035).

2⁶⁴⁰¹⁸⁰ is an apocalyptic number.

It is an amenable number.

640180 is an abundant number, since it is smaller than the sum of its proper divisors (704240).

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

640180 is a wasteful number, since it uses less digits than its factorization.

640180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32018 (or 32016 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 640180 is about 800.1124920910. The cubic root of 640180 is about 86.1854659741.

It can be divided in two parts, 640 and 180, that added together give a triangular number (820 = T₄₀).

The spelling of 640180 in words is "six hundred forty thousand, one hundred eighty".