3121 has 2 divisors, whose sum is σ = 3122. Its totient is φ = 3120.

The previous prime is 3119. The next prime is 3137. The reversal of 3121 is 1213.

3121 = 39² + 40².

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1600 + 1521 = 40^2 + 39^2 .

It is an emirp because it is prime and its reverse (1213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3121 - 2¹ = 3119 is a prime.

Together with 3119, it forms a pair of twin primes.

3121 is a lucky number.

It is a plaindrome in base 11 and base 14.

It is a nialpdrome in base 5, base 15 and base 16.

It is not a weakly prime, because it can be changed into another prime (3181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1560 + 1561.

It is an arithmetic number, because the mean of its divisors is an integer number (1561).

3121 is the 40-th centered square number.

It is an amenable number.

3121 is a deficient number, since it is larger than the sum of its proper divisors (1).

3121 is an equidigital number, since it uses as much as digits as its factorization.

3121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6, while the sum is 7.

The square root of 3121 is about 55.8659108939. The cubic root of 3121 is about 14.6138481232.

Adding to 3121 its reverse (1213), we get a palindrome (4334).

It can be divided in two parts, 312 and 1, that added together give a palindrome (313).

The spelling of 3121 in words is "three thousand, one hundred twenty-one", and thus it is an iban number.