30440 has 16 divisors (see below), whose sum is σ = 68580. Its totient is φ = 12160.

The previous prime is 30431. The next prime is 30449. The reversal of 30440 is 4403.

It is an interprime number because it is at equal distance from previous prime (30431) and next prime (30449).

It can be written as a sum of positive squares in 2 ways, for example, as 24964 + 5476 = 158^2 + 74^2 .

It is not an unprimeable number, because it can be changed into a prime (30449) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 341 + ... + 420.

2³⁰⁴⁴⁰ is an apocalyptic number.

It is an amenable number.

30440 is an abundant number, since it is smaller than the sum of its proper divisors (38140).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34290).

30440 is a wasteful number, since it uses less digits than its factorization.

30440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 772 (or 768 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 11.

The square root of 30440 is about 174.4706279005. The cubic root of 30440 is about 31.2234975302.

Adding to 30440 its reverse (4403), we get a palindrome (34843).

The spelling of 30440 in words is "thirty thousand, four hundred forty".