3121331221 has 8 divisors (see below), whose sum is σ = 3192593760. Its totient is φ = 3050680752.

The previous prime is 3121331203. The next prime is 3121331243. The reversal of 3121331221 is 1221331213.

3121331221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 3121331221 - 2⁷ = 3121331093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3121331201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 142695 + ... + 163108.

It is an arithmetic number, because the mean of its divisors is an integer number (399074220).

Almost surely, 2^3121331221 is an apocalyptic number.

It is an amenable number.

3121331221 is a deficient number, since it is larger than the sum of its proper divisors (71262539).

3121331221 is a wasteful number, since it uses less digits than its factorization.

3121331221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306035.

The product of its digits is 216, while the sum is 19.

The square root of 3121331221 is about 55868.8752437348. The cubic root of 3121331221 is about 1461.4365077355.

Adding to 3121331221 its reverse (1221331213), we get a palindrome (4342662434).

The spelling of 3121331221 in words is "three billion, one hundred twenty-one million, three hundred thirty-one thousand, two hundred twenty-one".