20001021021001 has 4 divisors (see below), whose sum is σ = 20043849760272. Its totient is φ = 19958192281732.

The previous prime is 20001021020993. The next prime is 20001021021077. The reversal of 20001021021001 is 10012012010002.

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 20001021021001 - 2³ = 20001021020993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20001021021301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21414368935 + ... + 21414369868.

It is an arithmetic number, because the mean of its divisors is an integer number (5010962440068).

Almost surely, 2^{20001021021001} is an apocalyptic number.

It is an amenable number.

20001021021001 is a deficient number, since it is larger than the sum of its proper divisors (42828739271).

20001021021001 is an equidigital number, since it uses as much as digits as its factorization.

20001021021001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42828739270.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 20001021021001 its reverse (10012012010002), we get a palindrome (30013033031003).

The spelling of 20001021021001 in words is "twenty trillion, one billion, twenty-one million, twenty-one thousand, one".