215305265 has 12 divisors (see below), whose sum is σ = 300548916. Its totient is φ = 147637728.

The previous prime is 215305249. The next prime is 215305267. The reversal of 215305265 is 562503512.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 97278769 + 118026496 = 9863^2 + 10864^2 .

It is not a de Polignac number, because 215305265 - 2⁴ = 215305249 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 (215305267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 439154 + ... + 439643.

It is an arithmetic number, because the mean of its divisors is an integer number (25045743).

Almost surely, 2^215305265 is an apocalyptic number.

It is an amenable number.

215305265 is a deficient number, since it is larger than the sum of its proper divisors (85243651).

215305265 is an equidigital number, since it uses as much as digits as its factorization.

215305265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 878816 (or 878809 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 29.

The square root of 215305265 is about 14673.2840564067. The cubic root of 215305265 is about 599.3560359496.

Adding to 215305265 its reverse (562503512), we get a palindrome (777808777).

The spelling of 215305265 in words is "two hundred fifteen million, three hundred five thousand, two hundred sixty-five".