1200121012021 has 4 divisors (see below), whose sum is σ = 1200333541312. Its totient is φ = 1199908482732.

The previous prime is 1200121012009. The next prime is 1200121012043. The reversal of 1200121012021 is 1202101210021.

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 1200121012021 - 2¹⁹ = 1200120487733 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1200121011992 and 1200121012010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1200121012061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106256175 + ... + 106267468.

It is an arithmetic number, because the mean of its divisors is an integer number (300083385328).

Almost surely, 2^{1200121012021} is an apocalyptic number.

It is an amenable number.

1200121012021 is a deficient number, since it is larger than the sum of its proper divisors (212529291).

1200121012021 is an equidigital number, since it uses as much as digits as its factorization.

1200121012021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212529290.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 1200121012021 its reverse (1202101210021), we get a palindrome (2402222222042).

The spelling of 1200121012021 in words is "one trillion, two hundred billion, one hundred twenty-one million, twelve thousand, twenty-one".