305215 has 4 divisors (see below), whose sum is σ = 366264. Its totient is φ = 244168.

The previous prime is 305209. The next prime is 305219. The reversal of 305215 is 512503.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 305215 - 2¹³ = 297023 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (305219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30517 + ... + 30526.

It is an arithmetic number, because the mean of its divisors is an integer number (91566).

2³⁰⁵²¹⁵ is an apocalyptic number.

305215 is a deficient number, since it is larger than the sum of its proper divisors (61049).

305215 is an equidigital number, since it uses as much as digits as its factorization.

305215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61048.

The product of its (nonzero) digits is 150, while the sum is 16.

The square root of 305215 is about 552.4626684220. The cubic root of 305215 is about 67.3289680099.

Adding to 305215 its reverse (512503), we get a palindrome (817718).

The spelling of 305215 in words is "three hundred five thousand, two hundred fifteen".