221215323 has 16 divisors (see below), whose sum is σ = 344263680. Its totient is φ = 123718656.

The previous prime is 221215321. The next prime is 221215327. The reversal of 221215323 is 323512122.

It is not a de Polignac number, because 221215323 - 2¹ = 221215321 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 221215323.

It is not an unprimeable number, because it can be changed into a prime (221215321) 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, 111078 + ... + 113051.

It is an arithmetic number, because the mean of its divisors is an integer number (21516480).

Almost surely, 2^221215323 is an apocalyptic number.

221215323 is a deficient number, since it is larger than the sum of its proper divisors (123048357).

221215323 is a wasteful number, since it uses less digits than its factorization.

221215323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224186.

The product of its digits is 720, while the sum is 21.

The square root of 221215323 is about 14873.3090803627. The cubic root of 221215323 is about 604.7906504225.

Adding to 221215323 its reverse (323512122), we get a palindrome (544727445).

The spelling of 221215323 in words is "two hundred twenty-one million, two hundred fifteen thousand, three hundred twenty-three".