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BaseRepresentation
bin1110110001
31022000
432301
512240
64213
72520
oct1661
91260
10945
1178a
12669
13579
144b7
15430
hex3b1

945 has 16 divisors (see below), whose sum is σ = 1920. Its totient is φ = 432.

The previous prime is 941. The next prime is 947. The reversal of 945 is 549.

It can be divided in two parts, 94 and 5, that added together give a palindrome (99).

It is a double factorial (945 = 9 !! = 1 ⋅ 3 ⋅ 5 ⋅ 7 ⋅ 9 ).

945 is nontrivially palindromic in base 8.

It is not a de Polignac number, because 945 - 22 = 941 is a prime.

It is a Leyland number of the form 63 + 36.

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

Its product of digits (180) is a multiple of the sum of its prime divisors (15).

It is a plaindrome in base 11, base 12 and base 13.

It is a nialpdrome in base 15.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 945.

It is not an unprimeable number, because it can be changed into a prime (941) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 132 + ... + 138.

It is an arithmetic number, because the mean of its divisors is an integer number (120).

It is an amenable number.

945 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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 (960).

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

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

The sum of its prime factors is 21 (or 15 counting only the distinct ones).

The product of its digits is 180, while the sum is 18.

The square root of 945 is about 30.7408522979. The cubic root of 945 is about 9.8131989306.

The spelling of 945 in words is "nine hundred forty-five", and thus it is an aban number.

Divisors: 1 3 5 7 9 15 21 27 35 45 63 105 135 189 315 945