221215393 has 16 divisors (see below), whose sum is σ = 262039680. Its totient is φ = 182722176.

The previous prime is 221215369. The next prime is 221215399. The reversal of 221215393 is 393512122.

It is not a de Polignac number, because 221215393 - 2⁵ = 221215361 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221215399) 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, 189630 + ... + 190792.

It is an arithmetic number, because the mean of its divisors is an integer number (16377480).

Almost surely, 2^221215393 is an apocalyptic number.

It is an amenable number.

221215393 is a deficient number, since it is larger than the sum of its proper divisors (40824287).

221215393 is a wasteful number, since it uses less digits than its factorization.

221215393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2136.

The product of its digits is 3240, while the sum is 28.

The square root of 221215393 is about 14873.3114335712. The cubic root of 221215393 is about 604.7907142146.

The spelling of 221215393 in words is "two hundred twenty-one million, two hundred fifteen thousand, three hundred ninety-three".