331111221 has 8 divisors (see below), whose sum is σ = 504550464. Its totient is φ = 189206400.

The previous prime is 331111213. The next prime is 331111237. The reversal of 331111221 is 122111133.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 331111221 - 2³ = 331111213 is a prime.

It is a super-2 number, since 2×331111221² = 219269281344221682, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 331111221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (331111211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7883580 + ... + 7883621.

It is an arithmetic number, because the mean of its divisors is an integer number (63068808).

Almost surely, 2^331111221 is an apocalyptic number.

It is an amenable number.

331111221 is a deficient number, since it is larger than the sum of its proper divisors (173439243).

331111221 is a wasteful number, since it uses less digits than its factorization.

331111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15767211.

The product of its digits is 36, while the sum is 15.

The square root of 331111221 is about 18196.4617714544. The cubic root of 331111221 is about 691.8171113075.

Adding to 331111221 its reverse (122111133), we get a palindrome (453222354).

It can be divided in two parts, 3311112 and 21, that added together give a palindrome (3311133).

The spelling of 331111221 in words is "three hundred thirty-one million, one hundred eleven thousand, two hundred twenty-one".