30985 has 4 divisors (see below), whose sum is σ = 37188. Its totient is φ = 24784.

The previous prime is 30983. The next prime is 31013. The reversal of 30985 is 58903.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11664 + 19321 = 108^2 + 139^2 .

It is a cyclic number.

It is not a de Polignac number, because 30985 - 2¹ = 30983 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a plaindrome in base 13.

It is a nialpdrome in base 8.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30983) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3094 + ... + 3103.

It is an arithmetic number, because the mean of its divisors is an integer number (9297).

2³⁰⁹⁸⁵ is an apocalyptic number.

It is an amenable number.

30985 is a deficient number, since it is larger than the sum of its proper divisors (6203).

30985 is an equidigital number, since it uses as much as digits as its factorization.

30985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6202.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 30985 is about 176.0255663249. The cubic root of 30985 is about 31.4087389635.

The spelling of 30985 in words is "thirty thousand, nine hundred eighty-five".