312612121 has 2 divisors, whose sum is σ = 312612122. Its totient is φ = 312612120.

The previous prime is 312612119. The next prime is 312612137. The reversal of 312612121 is 121216213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 261274896 + 51337225 = 16164^2 + 7165^2 .

It is a cyclic number.

It is not a de Polignac number, because 312612121 - 2¹ = 312612119 is a prime.

It is a super-2 number, since 2×312612121² = 195452676392237282, which contains 22 as substring.

Together with 312612119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (312612191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156306060 + 156306061.

It is an arithmetic number, because the mean of its divisors is an integer number (156306061).

Almost surely, 2^312612121 is an apocalyptic number.

It is an amenable number.

312612121 is a deficient number, since it is larger than the sum of its proper divisors (1).

312612121 is an equidigital number, since it uses as much as digits as its factorization.

312612121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 144, while the sum is 19.

The square root of 312612121 is about 17680.8405060393. The cubic root of 312612121 is about 678.6855526358.

Adding to 312612121 its reverse (121216213), we get a palindrome (433828334).

The spelling of 312612121 in words is "three hundred twelve million, six hundred twelve thousand, one hundred twenty-one".