305440 has 48 divisors (see below), whose sum is σ = 762048. Its totient is φ = 115456.

The previous prime is 305423. The next prime is 305441. The reversal of 305440 is 44503.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is not an unprimeable number, because it can be changed into a prime (305441) by changing a digit.

305440 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3639 + ... + 3721.

It is an arithmetic number, because the mean of its divisors is an integer number (15876).

2³⁰⁵⁴⁴⁰ 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 305440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (381024).

305440 is an abundant number, since it is smaller than the sum of its proper divisors (456608).

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

305440 is a wasteful number, since it uses less digits than its factorization.

305440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121 (or 113 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 16.

The square root of 305440 is about 552.6662645756. Note that the first 3 decimals coincide. The cubic root of 305440 is about 67.3455085870.

Adding to 305440 its reverse (44503), we get a palindrome (349943).

The spelling of 305440 in words is "three hundred five thousand, four hundred forty".