121221020121 has 4 divisors (see below), whose sum is σ = 161628026832. Its totient is φ = 80814013412.

The previous prime is 121221020117. The next prime is 121221020189. The reversal of 121221020121 is 121020122121.

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 not a de Polignac number, because 121221020121 - 2² = 121221020117 is a prime.

It is a super-3 number, since 3×121221020121³ (a number of 34 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 121221020121.

It is not an unprimeable number, because it can be changed into a prime (121221020821) 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, 20203503351 + ... + 20203503356.

It is an arithmetic number, because the mean of its divisors is an integer number (40407006708).

Almost surely, 2^121221020121 is an apocalyptic number.

It is an amenable number.

121221020121 is a deficient number, since it is larger than the sum of its proper divisors (40407006711).

121221020121 is an equidigital number, since it uses as much as digits as its factorization.

121221020121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40407006710.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 121221020121 its reverse (121020122121), we get a palindrome (242241142242).

The spelling of 121221020121 in words is "one hundred twenty-one billion, two hundred twenty-one million, twenty thousand, one hundred twenty-one".