30840 has 32 divisors (see below), whose sum is σ = 92880. Its totient is φ = 8192.

The previous prime is 30839. The next prime is 30841. The reversal of 30840 is 4803.

30840 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

30840 is an esthetic number in base 16, because in such base its adjacent digits differ by 1.

It is an interprime number because it is at equal distance from previous prime (30839) and next prime (30841).

It is a super-2 number, since 2×30840² = 1902211200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

30840 is an undulating number in base 16.

It is a nialpdrome in base 15.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30841) by changing a digit.

In principle, a polygon with 30840 sides can be constructed with ruler and compass.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9 + ... + 248.

2³⁰⁸⁴⁰ is an apocalyptic number.

30840 is a gapful number since it is divisible by the number (30) 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 30840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46440).

30840 is an abundant number, since it is smaller than the sum of its proper divisors (62040).

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

30840 is a wasteful number, since it uses less digits than its factorization.

30840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271 (or 267 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 30840 is about 175.6132113481. The cubic root of 30840 is about 31.3596680168.

It can be divided in two parts, 30 and 840, that multiplied together give a triangular number (25200 = T₂₂₄).

The spelling of 30840 in words is "thirty thousand, eight hundred forty".