1001001101021 has 4 divisors (see below), whose sum is σ = 1001123048700. Its totient is φ = 1000879153344.

The previous prime is 1001001101003. The next prime is 1001001101071. The reversal of 1001001101021 is 1201011001001.

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 50933719225 + 950067381796 = 225685^2 + 974714^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001001101021 - 2¹⁰ = 1001001099997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001001101071) 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, 60961526 + ... + 60977943.

It is an arithmetic number, because the mean of its divisors is an integer number (250280762175).

Almost surely, 2^{1001001101021} is an apocalyptic number.

It is an amenable number.

1001001101021 is a deficient number, since it is larger than the sum of its proper divisors (121947679).

1001001101021 is an equidigital number, since it uses as much as digits as its factorization.

1001001101021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121947678.

The product of its (nonzero) digits is 2, while the sum is 8.

Adding to 1001001101021 its reverse (1201011001001), we get a palindrome (2202012102022).

The spelling of 1001001101021 in words is "one trillion, one billion, one million, one hundred one thousand, twenty-one".