3121221321 has 12 divisors (see below), whose sum is σ = 4630280772. Its totient is φ = 2024575776.

The previous prime is 3121221287. The next prime is 3121221373. The reversal of 3121221321 is 1231221213.

3121221321 is a `hidden beast` number, since 3 + 121 + 221 + 321 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 2760031296 + 361190025 = 52536^2 + 19005^2 .

It is not a de Polignac number, because 3121221321 - 2¹¹ = 3121219273 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 3121221294 and 3121221303.

It is not an unprimeable number, because it can be changed into a prime (3121221121) 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, 4686186 + ... + 4686851.

It is an arithmetic number, because the mean of its divisors is an integer number (385856731).

Almost surely, 2^3121221321 is an apocalyptic number.

It is an amenable number.

3121221321 is a deficient number, since it is larger than the sum of its proper divisors (1509059451).

3121221321 is a wasteful number, since it uses less digits than its factorization.

3121221321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9373080 (or 9373077 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 3121221321 is about 55867.8916820744. The cubic root of 3121221321 is about 1461.4193554645.

Adding to 3121221321 its reverse (1231221213), we get a palindrome (4352442534).

The spelling of 3121221321 in words is "three billion, one hundred twenty-one million, two hundred twenty-one thousand, three hundred twenty-one".