331221345 has 64 divisors (see below), whose sum is σ = 654925824. Its totient is φ = 139196160.

The previous prime is 331221337. The next prime is 331221347. The reversal of 331221345 is 543122133.

It is not a de Polignac number, because 331221345 - 2³ = 331221337 is a prime.

It is not an unprimeable number, because it can be changed into a prime (331221347) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 588034 + ... + 588596.

It is an arithmetic number, because the mean of its divisors is an integer number (10233216).

Almost surely, 2^331221345 is an apocalyptic number.

331221345 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

331221345 is a deficient number, since it is larger than the sum of its proper divisors (323704479).

331221345 is a wasteful number, since it uses less digits than its factorization.

331221345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1022.

The product of its digits is 2160, while the sum is 24.

The square root of 331221345 is about 18199.4874927840. The cubic root of 331221345 is about 691.8937997616.

Adding to 331221345 its reverse (543122133), we get a palindrome (874343478).

The spelling of 331221345 in words is "three hundred thirty-one million, two hundred twenty-one thousand, three hundred forty-five".