213717305 has 8 divisors (see below), whose sum is σ = 256574472. Its totient is φ = 170898048.

The previous prime is 213717277. The next prime is 213717307. The reversal of 213717305 is 503717312.

213717305 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 29735209 + 183982096 = 5453^2 + 13564^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 213717305 - 2⁶ = 213717241 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (213717307) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4919 + ... + 21251.

It is an arithmetic number, because the mean of its divisors is an integer number (32071809).

Almost surely, 2^213717305 is an apocalyptic number.

It is an amenable number.

213717305 is a deficient number, since it is larger than the sum of its proper divisors (42857167).

213717305 is a wasteful number, since it uses less digits than its factorization.

213717305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18955.

The product of its (nonzero) digits is 4410, while the sum is 29.

The square root of 213717305 is about 14619.0733290452. The cubic root of 213717305 is about 597.8789039404.

The spelling of 213717305 in words is "two hundred thirteen million, seven hundred seventeen thousand, three hundred five".