213105517 has 2 divisors, whose sum is σ = 213105518. Its totient is φ = 213105516.

The previous prime is 213105499. The next prime is 213105521. The reversal of 213105517 is 715501312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 196953156 + 16152361 = 14034^2 + 4019^2 .

It is a cyclic number.

It is not a de Polignac number, because 213105517 - 2¹⁵ = 213072749 is a prime.

It is a super-4 number, since 4×213105517⁴ (a number of 34 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 213105491 and 213105500.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213105547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106552758 + 106552759.

It is an arithmetic number, because the mean of its divisors is an integer number (106552759).

Almost surely, 2^213105517 is an apocalyptic number.

It is an amenable number.

213105517 is a deficient number, since it is larger than the sum of its proper divisors (1).

213105517 is an equidigital number, since it uses as much as digits as its factorization.

213105517 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1050, while the sum is 25.

The square root of 213105517 is about 14598.1340245937. The cubic root of 213105517 is about 597.3078618682.

Adding to 213105517 its reverse (715501312), we get a palindrome (928606829).

The spelling of 213105517 in words is "two hundred thirteen million, one hundred five thousand, five hundred seventeen".