221266215 has 64 divisors (see below), whose sum is σ = 405390720. Its totient is φ = 114462720.

The previous prime is 221266183. The next prime is 221266247. The reversal of 221266215 is 512662122.

221266215 is a `hidden beast` number, since 22 + 12 + 6 + 621 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (221266183) and next prime (221266247).

It is not a de Polignac number, because 221266215 - 2⁵ = 221266183 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 798657 + ... + 798933.

It is an arithmetic number, because the mean of its divisors is an integer number (6334230).

Almost surely, 2^221266215 is an apocalyptic number.

221266215 is a deficient number, since it is larger than the sum of its proper divisors (184124505).

221266215 is a wasteful number, since it uses less digits than its factorization.

221266215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 449 (or 443 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 221266215 is about 14875.0198319196. The cubic root of 221266215 is about 604.8370255189.

The spelling of 221266215 in words is "two hundred twenty-one million, two hundred sixty-six thousand, two hundred fifteen".