440640 has 140 divisors (see below), whose sum is σ = 1659636. Its totient is φ = 110592.

The previous prime is 440581. The next prime is 440641. The reversal of 440640 is 46044.

It can be written as a sum of positive squares in 2 ways, for example, as 254016 + 186624 = 504^2 + 432^2 .

It is a hoax number, since the sum of its digits (18) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Saint-Exupery number, since it is equal to the product of the sides of a Pythagorean triangle: 102 × 90 × 48.

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 440640.

It is not an unprimeable number, because it can be changed into a prime (440641) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 25912 + ... + 25928.

2⁴⁴⁰⁶⁴⁰ is an apocalyptic number.

440640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 440640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (829818).

440640 is an abundant number, since it is smaller than the sum of its proper divisors (1218996).

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

440640 is a wasteful number, since it uses less digits than its factorization.

440640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46 (or 27 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 440640 is about 663.8072009251. The cubic root of 440640 is about 76.0959084646.

Adding to 440640 its reverse (46044), we get a palindrome (486684).

The spelling of 440640 in words is "four hundred forty thousand, six hundred forty".