343640 has 48 divisors (see below), whose sum is σ = 861840. Its totient is φ = 123200.

The previous prime is 343639. The next prime is 343649. The reversal of 343640 is 46343.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an Ulam number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 343640.

It is not an unprimeable number, because it can be changed into a prime (343649) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4805 + ... + 4875.

It is an arithmetic number, because the mean of its divisors is an integer number (17955).

2³⁴³⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 343640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (430920).

343640 is an abundant number, since it is smaller than the sum of its proper divisors (518200).

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

343640 is a wasteful number, since it uses less digits than its factorization.

343640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104 (or 89 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 20.

The square root of 343640 is about 586.2081541569. The cubic root of 343640 is about 70.0435103643.

Adding to 343640 its reverse (46343), we get a palindrome (389983).

The spelling of 343640 in words is "three hundred forty-three thousand, six hundred forty".