331221121 has 16 divisors (see below), whose sum is σ = 413366400. Its totient is φ = 257834880.

The previous prime is 331221119. The next prime is 331221127. The reversal of 331221121 is 121122133.

It is a cyclic number.

It is not a de Polignac number, because 331221121 - 2¹ = 331221119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 331221095 and 331221104.

It is not an unprimeable number, because it can be changed into a prime (331221127) 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, 117885 + ... + 120661.

It is an arithmetic number, because the mean of its divisors is an integer number (25835400).

Almost surely, 2^331221121 is an apocalyptic number.

It is an amenable number.

331221121 is a deficient number, since it is larger than the sum of its proper divisors (82145279).

331221121 is a wasteful number, since it uses less digits than its factorization.

331221121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4344.

The product of its digits is 72, while the sum is 16.

The square root of 331221121 is about 18199.4813387635. The cubic root of 331221121 is about 691.8936437891.

Adding to 331221121 its reverse (121122133), we get a palindrome (452343254).

It can be divided in two parts, 33122 and 1121, that added together give a palindrome (34243).

The spelling of 331221121 in words is "three hundred thirty-one million, two hundred twenty-one thousand, one hundred twenty-one".