30805 has 8 divisors (see below), whose sum is σ = 37944. Its totient is φ = 24000.

The previous prime is 30803. The next prime is 30809. The reversal of 30805 is 50803.

It can be written as a sum of positive squares in 4 ways, for example, as 2916 + 27889 = 54^2 + 167^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 30805 - 2¹ = 30803 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30803) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 255 + ... + 355.

It is an arithmetic number, because the mean of its divisors is an integer number (4743).

2³⁰⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

30805 is a deficient number, since it is larger than the sum of its proper divisors (7139).

30805 is a wasteful number, since it uses less digits than its factorization.

30805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 30805 is about 175.5135322418. The cubic root of 30805 is about 31.3478002708.

It can be divided in two parts, 3080 and 5, that multiplied together give a triangular number (15400 = T₁₇₅).

The spelling of 30805 in words is "thirty thousand, eight hundred five".