340640 has 24 divisors (see below), whose sum is σ = 805140. Its totient is φ = 136192.

The previous prime is 340633. The next prime is 340643. The reversal of 340640 is 46043.

It can be written as a sum of positive squares in 2 ways, for example, as 327184 + 13456 = 572^2 + 116^2 .

It is not an unprimeable number, because it can be changed into a prime (340643) 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, 905 + ... + 1224.

2³⁴⁰⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

340640 is an abundant number, since it is smaller than the sum of its proper divisors (464500).

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

340640 is a wasteful number, since it uses less digits than its factorization.

340640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2144 (or 2136 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 17.

The square root of 340640 is about 583.6437269431. The cubic root of 340640 is about 69.8390861620.

Adding to 340640 its reverse (46043), we get a palindrome (386683).

The spelling of 340640 in words is "three hundred forty thousand, six hundred forty".