20201021001 has 40 divisors (see below), whose sum is σ = 36516522240. Its totient is φ = 10864409472.

The previous prime is 20201020969. The next prime is 20201021021. The reversal of 20201021001 is 10012010202.

It is not a de Polignac number, because 20201021001 - 2⁵ = 20201020969 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (20201021021) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1038241 + ... + 1057518.

It is an arithmetic number, because the mean of its divisors is an integer number (912913056).

Almost surely, 2^20201021001 is an apocalyptic number.

20201021001 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20201021001 is a deficient number, since it is larger than the sum of its proper divisors (16315501239).

20201021001 is a wasteful number, since it uses less digits than its factorization.

20201021001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2095795 (or 2095786 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 20201021001 its reverse (10012010202), we get a palindrome (30213031203).

The spelling of 20201021001 in words is "twenty billion, two hundred one million, twenty-one thousand, one".