20201021202021 has 16 divisors (see below), whose sum is σ = 29436056382528. Its totient is φ = 12221062812800.

The previous prime is 20201021201953. The next prime is 20201021202023. The reversal of 20201021202021 is 12020212010202.

It is a cyclic number.

It is not a de Polignac number, because 20201021202021 - 2¹⁸ = 20201020939877 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20201021202023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 549489840 + ... + 549526601.

It is an arithmetic number, because the mean of its divisors is an integer number (1839753523908).

Almost surely, 2^{20201021202021} is an apocalyptic number.

It is an amenable number.

20201021202021 is a deficient number, since it is larger than the sum of its proper divisors (9235035180507).

20201021202021 is a wasteful number, since it uses less digits than its factorization.

20201021202021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1099017012.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 20201021202021 its reverse (12020212010202), we get a palindrome (32221233212223).

The spelling of 20201021202021 in words is "twenty trillion, two hundred one billion, twenty-one million, two hundred two thousand, twenty-one".