215002221 has 16 divisors (see below), whose sum is σ = 328310784. Its totient is φ = 122600304.

The previous prime is 215002217. The next prime is 215002243. The reversal of 215002221 is 122200512.

215002221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 215002221 - 2² = 215002217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 215002221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215002211) 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, 285 + ... + 20738.

It is an arithmetic number, because the mean of its divisors is an integer number (20519424).

Almost surely, 2^215002221 is an apocalyptic number.

215002221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

215002221 is a deficient number, since it is larger than the sum of its proper divisors (113308563).

215002221 is a wasteful number, since it uses less digits than its factorization.

215002221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21520.

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 215002221 is about 14662.9540338910. The cubic root of 215002221 is about 599.0747043356.

Adding to 215002221 its reverse (122200512), we get a palindrome (337202733).

The spelling of 215002221 in words is "two hundred fifteen million, two thousand, two hundred twenty-one".