121200021021 has 12 divisors (see below), whose sum is σ = 163436192192. Its totient is φ = 79892133024.

The previous prime is 121200020989. The next prime is 121200021023. The reversal of 121200021021 is 120120002121.

It is not a de Polignac number, because 121200021021 - 2⁵ = 121200020989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121200020988 and 121200021006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121200021023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2526421 + ... + 2573946.

Almost surely, 2^121200021021 is an apocalyptic number.

It is an amenable number.

121200021021 is a deficient number, since it is larger than the sum of its proper divisors (42236171171).

121200021021 is an frugal number, since it uses more digits than its factorization.

121200021021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5100548 (or 5100459 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 121200021021 its reverse (120120002121), we get a palindrome (241320023142).

The spelling of 121200021021 in words is "one hundred twenty-one billion, two hundred million, twenty-one thousand, twenty-one".