1200120021121 has 6 divisors (see below), whose sum is σ = 1396057983810. Its totient is φ = 1028674303776.

The previous prime is 1200120021109. The next prime is 1200120021157. The reversal of 1200120021121 is 1211200210021.

It can be written as a sum of positive squares in only one way, i.e., 790569939600 + 409550081521 = 889140^2 + 639961^2 .

It is not a de Polignac number, because 1200120021121 - 2¹¹ = 1200120019073 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1200120021181) 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 5 ways as a sum of consecutive naturals, for example, 12246122616 + ... + 12246122713.

It is an arithmetic number, because the mean of its divisors is an integer number (232676330635).

Almost surely, 2^{1200120021121} is an apocalyptic number.

It is an amenable number.

1200120021121 is a deficient number, since it is larger than the sum of its proper divisors (195937962689).

1200120021121 is an equidigital number, since it uses as much as digits as its factorization.

1200120021121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24492245343 (or 24492245336 counting only the distinct ones).

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

Adding to 1200120021121 its reverse (1211200210021), we get a palindrome (2411320231142).

The spelling of 1200120021121 in words is "one trillion, two hundred billion, one hundred twenty million, twenty-one thousand, one hundred twenty-one".