221123210 has 32 divisors (see below), whose sum is σ = 496236672. Its totient is φ = 68921280.

The previous prime is 221123191. The next prime is 221123213. The reversal of 221123210 is 12321122.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is not an unprimeable number, because it can be changed into a prime (221123213) 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, 142817 + ... + 144356.

It is an arithmetic number, because the mean of its divisors is an integer number (15507396).

Almost surely, 2^221123210 is an apocalyptic number.

221123210 is an abundant number, since it is smaller than the sum of its proper divisors (275113462).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221123210 is a wasteful number, since it uses less digits than its factorization.

221123210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 287198.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 221123210 is about 14870.2121706450. The cubic root of 221123210 is about 604.7066947927.

Adding to 221123210 its reverse (12321122), we get a palindrome (233444332).

The spelling of 221123210 in words is "two hundred twenty-one million, one hundred twenty-three thousand, two hundred ten".