1200020201021 has 4 divisors (see below), whose sum is σ = 1200023468412. Its totient is φ = 1200016933632.

The previous prime is 1200020200997. The next prime is 1200020201053. The reversal of 1200020201021 is 1201020200021.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 835004853796 + 365015347225 = 913786^2 + 604165^2 .

It is a cyclic number.

It is not a de Polignac number, because 1200020201021 - 2¹⁴ = 1200020184637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1200020200993 and 1200020201011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1200020201321) 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, 1001150 + ... + 1844543.

It is an arithmetic number, because the mean of its divisors is an integer number (300005867103).

Almost surely, 2^{1200020201021} is an apocalyptic number.

It is an amenable number.

1200020201021 is a deficient number, since it is larger than the sum of its proper divisors (3267391).

1200020201021 is an equidigital number, since it uses as much as digits as its factorization.

1200020201021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3267390.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 1200020201021 its reverse (1201020200021), we get a palindrome (2401040401042).

It can be divided in two parts, 1200020 and 201021, that added together give a palindrome (1401041).

The spelling of 1200020201021 in words is "one trillion, two hundred billion, twenty million, two hundred one thousand, twenty-one".