215221215 has 16 divisors (see below), whose sum is σ = 375659136. Its totient is φ = 104349600.

The previous prime is 215221213. The next prime is 215221229. The reversal of 215221215 is 512122512.

It is not a de Polignac number, because 215221215 - 2¹ = 215221213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 215221191 and 215221200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215221211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 652021 + ... + 652350.

It is an arithmetic number, because the mean of its divisors is an integer number (23478696).

Almost surely, 2^215221215 is an apocalyptic number.

215221215 is a deficient number, since it is larger than the sum of its proper divisors (160437921).

215221215 is a wasteful number, since it uses less digits than its factorization.

215221215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1304390.

The product of its digits is 400, while the sum is 21.

The square root of 215221215 is about 14670.4197281468. The cubic root of 215221215 is about 599.2780344023.

Adding to 215221215 its reverse (512122512), we get a palindrome (727343727).

The spelling of 215221215 in words is "two hundred fifteen million, two hundred twenty-one thousand, two hundred fifteen".