121210321 has 4 divisors (see below), whose sum is σ = 123789312. Its totient is φ = 118631332.

The previous prime is 121210237. The next prime is 121210333. The reversal of 121210321 is 123012121.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121210321 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 (121210351) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1289425 + ... + 1289518.

It is an arithmetic number, because the mean of its divisors is an integer number (30947328).

Almost surely, 2^121210321 is an apocalyptic number.

It is an amenable number.

121210321 is a deficient number, since it is larger than the sum of its proper divisors (2578991).

121210321 is an equidigital number, since it uses as much as digits as its factorization.

121210321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2578990.

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

The square root of 121210321 is about 11009.5558947671. Note that the first 3 decimals coincide. The cubic root of 121210321 is about 494.8951531160.

Adding to 121210321 its reverse (123012121), we get a palindrome (244222442).

The spelling of 121210321 in words is "one hundred twenty-one million, two hundred ten thousand, three hundred twenty-one".