221313243 has 16 divisors (see below), whose sum is σ = 304899840. Its totient is φ = 142682976.

The previous prime is 221313241. The next prime is 221313251. The reversal of 221313243 is 342313122.

It is not a de Polignac number, because 221313243 - 2¹ = 221313241 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221313241) 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, 12568 + ... + 24506.

It is an arithmetic number, because the mean of its divisors is an integer number (19056240).

Almost surely, 2^221313243 is an apocalyptic number.

221313243 is a deficient number, since it is larger than the sum of its proper divisors (83586597).

221313243 is a wasteful number, since it uses less digits than its factorization.

221313243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12146.

The product of its digits is 864, while the sum is 21.

The square root of 221313243 is about 14876.6005189358. The cubic root of 221313243 is about 604.8798732423.

Adding to 221313243 its reverse (342313122), we get a palindrome (563626365).

The spelling of 221313243 in words is "two hundred twenty-one million, three hundred thirteen thousand, two hundred forty-three".