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3215 = 5643

3215 has 4 divisors (see below), whose sum is σ = 3864. Its totient is φ = 2568.

The previous prime is 3209. The next prime is 3217. The reversal of 3215 is 5123.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5123 = 47109.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2k-3215 is a prime.

It is a d-powerful number, because it can be written as 34 + 1 + 23 + 55 .

It is a Duffinian number.

It is a plaindrome in base 14.

It is a junction number, because it is equal to n+sod(n) for n = 3196 and 3205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3217) 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, 317 + ... + 326.

It is an arithmetic number, because the mean of its divisors is an integer number (966).

23215 is an apocalyptic number.

3215 is a deficient number, since it is larger than the sum of its proper divisors (649).

3215 is an equidigital number, since it uses as much as digits as its factorization.

3215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 648.

The product of its digits is 30, while the sum is 11.

The square root of 3215 is about 56.7009700093. The cubic root of 3215 is about 14.7591153080.

Adding to 3215 its reverse (5123), we get a palindrome (8338).

The spelling of 3215 in words is "three thousand, two hundred fifteen".

Divisors: 1 5 643 3215