221231121 has 16 divisors (see below), whose sum is σ = 303330048. Its totient is φ = 143337600.

The previous prime is 221231077. The next prime is 221231137. The reversal of 221231121 is 121132122.

221231121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221231121 - 2¹³ = 221222929 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221231121.

It is not an unprimeable number, because it can be changed into a prime (221231191) 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, 30015 + ... + 36651.

It is an arithmetic number, because the mean of its divisors is an integer number (18958128).

Almost surely, 2^221231121 is an apocalyptic number.

It is an amenable number.

221231121 is a deficient number, since it is larger than the sum of its proper divisors (82098927).

221231121 is a wasteful number, since it uses less digits than its factorization.

221231121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6952.

The product of its digits is 48, while the sum is 15.

The square root of 221231121 is about 14873.8401564626. The cubic root of 221231121 is about 604.8050470372.

Adding to 221231121 its reverse (121132122), we get a palindrome (342363243).

It can be divided in two parts, 2212 and 31121, that added together give a palindrome (33333).

The spelling of 221231121 in words is "two hundred twenty-one million, two hundred thirty-one thousand, one hundred twenty-one".