180440 has 32 divisors (see below), whose sum is σ = 438480. Its totient is φ = 66432.

The previous prime is 180437. The next prime is 180463. The reversal of 180440 is 44081.

180440 = 2² + 3² + ... + 81².

It is a happy number.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 347 + ... + 693.

2¹⁸⁰⁴⁴⁰ is an apocalyptic number.

180440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

180440 is the 347-th pentagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 180440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (219240).

180440 is an abundant number, since it is smaller than the sum of its proper divisors (258040).

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

180440 is a wasteful number, since it uses less digits than its factorization.

180440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 371 (or 367 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 180440 is about 424.7822971829. The cubic root of 180440 is about 56.5081305030.

The spelling of 180440 in words is "one hundred eighty thousand, four hundred forty".