331145221 has 16 divisors (see below), whose sum is σ = 370679040. Its totient is φ = 293244480.

The previous prime is 331145209. The next prime is 331145231. The reversal of 331145221 is 122541133.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 331145221 - 2¹³ = 331137029 is a prime.

It is a super-2 number, since 2×331145221² = 219314314782277682, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 331145192 and 331145201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (331145231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 116995 + ... + 119791.

It is an arithmetic number, because the mean of its divisors is an integer number (23167440).

Almost surely, 2^331145221 is an apocalyptic number.

It is an amenable number.

331145221 is a deficient number, since it is larger than the sum of its proper divisors (39533819).

331145221 is a wasteful number, since it uses less digits than its factorization.

331145221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3084.

The product of its digits is 720, while the sum is 22.

The square root of 331145221 is about 18197.3959950318. The cubic root of 331145221 is about 691.8407901353.

Adding to 331145221 its reverse (122541133), we get a palindrome (453686354).

The spelling of 331145221 in words is "three hundred thirty-one million, one hundred forty-five thousand, two hundred twenty-one".