215212225 has 6 divisors (see below), whose sum is σ = 266863190. Its totient is φ = 172169760.

The previous prime is 215212223. The next prime is 215212267. The reversal of 215212225 is 522212512.

It can be written as a sum of positive squares in 3 ways, for example, as 62001 + 215150224 = 249^2 + 14668^2 .

It is not a de Polignac number, because 215212225 - 2¹ = 215212223 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 215212196 and 215212205.

It is not an unprimeable number, because it can be changed into a prime (215212223) 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 5 ways as a sum of consecutive naturals, for example, 4304220 + ... + 4304269.

Almost surely, 2^215212225 is an apocalyptic number.

215212225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

215212225 is a deficient number, since it is larger than the sum of its proper divisors (51650965).

215212225 is an equidigital number, since it uses as much as digits as its factorization.

215212225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8608499 (or 8608494 counting only the distinct ones).

The product of its digits is 800, while the sum is 22.

The square root of 215212225 is about 14670.1133260790. The cubic root of 215212225 is about 599.2696901436.

Adding to 215212225 its reverse (522212512), we get a palindrome (737424737).

The spelling of 215212225 in words is "two hundred fifteen million, two hundred twelve thousand, two hundred twenty-five".