213517 has 4 divisors (see below), whose sum is σ = 215100. Its totient is φ = 211936.

The previous prime is 213491. The next prime is 213523. The reversal of 213517 is 715312.

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 98596 + 114921 = 314^2 + 339^2 .

It is a cyclic number.

It is not a de Polignac number, because 213517 - 2¹¹ = 211469 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 213494 and 213503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213557) 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, 568 + ... + 865.

It is an arithmetic number, because the mean of its divisors is an integer number (53775).

2²¹³⁵¹⁷ is an apocalyptic number.

It is an amenable number.

213517 is a deficient number, since it is larger than the sum of its proper divisors (1583).

213517 is a wasteful number, since it uses less digits than its factorization.

213517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1582.

The product of its digits is 210, while the sum is 19.

The square root of 213517 is about 462.0789975751. The cubic root of 213517 is about 59.7692059661.

Adding to 213517 its reverse (715312), we get a palindrome (928829).

The spelling of 213517 in words is "two hundred thirteen thousand, five hundred seventeen".