331431221 has 12 divisors (see below), whose sum is σ = 364743456. Its totient is φ = 300934920.

The previous prime is 331431203. The next prime is 331431223. The reversal of 331431221 is 122134133.

It is not a de Polignac number, because 331431221 - 2¹⁸ = 331169077 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 331431193 and 331431202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (331431223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 178520 + ... + 180366.

It is an arithmetic number, because the mean of its divisors is an integer number (30395288).

Almost surely, 2^331431221 is an apocalyptic number.

It is an amenable number.

331431221 is a deficient number, since it is larger than the sum of its proper divisors (33312235).

331431221 is a wasteful number, since it uses less digits than its factorization.

331431221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3352 (or 3341 counting only the distinct ones).

The product of its digits is 432, while the sum is 20.

The square root of 331431221 is about 18205.2525662238. The cubic root of 331431221 is about 692.0399067333.

Adding to 331431221 its reverse (122134133), we get a palindrome (453565354).

The spelling of 331431221 in words is "three hundred thirty-one million, four hundred thirty-one thousand, two hundred twenty-one".