3121004221 has 2 divisors, whose sum is σ = 3121004222. Its totient is φ = 3121004220.

The previous prime is 3121004219. The next prime is 3121004231. The reversal of 3121004221 is 1224001213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2476555225 + 644448996 = 49765^2 + 25386^2 .

It is a cyclic number.

It is not a de Polignac number, because 3121004221 - 2¹ = 3121004219 is a prime.

Together with 3121004219, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 3121004195 and 3121004204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3121004231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1560502110 + 1560502111.

It is an arithmetic number, because the mean of its divisors is an integer number (1560502111).

Almost surely, 2^3121004221 is an apocalyptic number.

It is an amenable number.

3121004221 is a deficient number, since it is larger than the sum of its proper divisors (1).

3121004221 is an equidigital number, since it uses as much as digits as its factorization.

3121004221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 3121004221 is about 55865.9486717983. The cubic root of 3121004221 is about 1461.3854711325.

Adding to 3121004221 its reverse (1224001213), we get a palindrome (4345005434).

The spelling of 3121004221 in words is "three billion, one hundred twenty-one million, four thousand, two hundred twenty-one".