1365 has 16 divisors (see below), whose sum is σ = 2688. Its totient is φ = 576.

The previous prime is 1361. The next prime is 1367. The reversal of 1365 is 5631.

1365 is nontrivially palindromic in base 2, base 4, base 12 and base 16.

1365 is an esthetic number in base 2, because in such base its adjacent digits differ by 1.

1365 is a nontrivial binomial coefficient, being equal to C(15, 4).

It is not a de Polignac number, because 1365 - 2^{2} = 1361 is a prime.

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

1365 is an idoneal number.

It is the 12-th Jacobsthal number.

1365 is an undulating number in base 2, base 8 and base 12.

It is a Curzon number.

1365 is a lucky number.

1365 is a nontrivial repdigit in base 4 and base 16.

It is a plaindrome in base 4 and base 16.

It is a nialpdrome in base 4, base 13, base 15 and base 16.

It is a zygodrome in base 4 and base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1361) by changing a digit.

It is a nontrivial repunit in base 4.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 99 + ... + 111.

It is an arithmetic number, because the mean of its divisors is an integer number (168).

1365 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1365 is a deficient number, since it is larger than the sum of its proper divisors (1323).

1365 is a wasteful number, since it uses less digits than its factorization.

1365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28.

The product of its digits is 90, while the sum is 15.

The square root of 1365 is about 36.9459064038. The cubic root of 1365 is about 11.0928775020.

1365 divided by its sum of digits (15) gives a triangular number (91 = T_{13}).

Subtracting from 1365 its product of digits (90), we obtain a triangular number (1275 = T_{50}).

Adding to 1365 its reverse (5631), we get a palindrome (6996).

It can be divided in two parts, 136 and 5, that added together give a palindrome (141).

The spelling of 1365 in words is "one thousand, three hundred sixty-five".

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