103212121 has 4 divisors (see below), whose sum is σ = 103232512. Its totient is φ = 103191732.

The previous prime is 103212103. The next prime is 103212163. The reversal of 103212121 is 121212301.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 121212301 = 7 ⋅17316043.

It is a cyclic number.

It is not a de Polignac number, because 103212121 - 2¹⁹ = 102687833 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (103212191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3820 + ... + 14866.

It is an arithmetic number, because the mean of its divisors is an integer number (25808128).

Almost surely, 2^103212121 is an apocalyptic number.

It is an amenable number.

103212121 is a deficient number, since it is larger than the sum of its proper divisors (20391).

103212121 is an equidigital number, since it uses as much as digits as its factorization.

103212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20390.

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 103212121 is about 10159.3366417301. The cubic root of 103212121 is about 469.0763829203.

Adding to 103212121 its reverse (121212301), we get a palindrome (224424422).

The spelling of 103212121 in words is "one hundred three million, two hundred twelve thousand, one hundred twenty-one".