• 385 can be written using four 4's:

385 has 8 divisors (see below), whose sum is σ = 576. Its totient is φ = 240.

The previous prime is 383. The next prime is 389. The reversal of 385 is 583.

385 = 1^{2} + 2^{2} + ... + 10^{2}.

385 is nontrivially palindromic in base 6 and base 16.

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

It is a Cullen number, since it is equal to 6×2^{6}+1.

It is not a de Polignac number, because 385 - 2^{1} = 383 is a prime.

385 is an idoneal number.

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

It is a Duffinian number.

385 is an undulating number in base 16.

It is a partition number, being equal to the number of ways a set of 18 identical objects can be partitioned into subset.

385 is a lucky number.

It is a plaindrome in base 9, base 13 and base 15.

It is a nialpdrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (3) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30 + ... + 40.

It is an arithmetic number, because the mean of its divisors is an integer number (72).

It is a Proth number, since it is equal to 3 ⋅ 2^{7} + 1 and 3 < 2^{7}.

385 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

385 is a deficient number, since it is larger than the sum of its proper divisors (191).

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

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

The sum of its prime factors is 23.

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

The square root of 385 is about 19.6214168703. The cubic root of 385 is about 7.2747863488.

Adding to 385 its product of digits (120), we get a palindrome (505).

It can be divided in two parts, 38 and 5, that multiplied together give a triangular number (190 = T_{19}).

The spelling of 385 in words is "three hundred eighty-five", and thus it is an aban number and an oban number.

• e-mail: info -at- numbersaplenty.com • Privacy notice • done in 0.118 sec. • engine limits •