2021100001 has 4 divisors (see below), whose sum is σ = 2022439104. Its totient is φ = 2019760900.

The previous prime is 2021099989. The next prime is 2021100019. The reversal of 2021100001 is 1000011202.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1000011202 = 2 ⋅500005601.

It is a cyclic number.

It is not a de Polignac number, because 2021100001 - 2²¹ = 2019002849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2021100041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 667285 + ... + 670306.

It is an arithmetic number, because the mean of its divisors is an integer number (505609776).

Almost surely, 2^2021100001 is an apocalyptic number.

It is an amenable number.

2021100001 is a deficient number, since it is larger than the sum of its proper divisors (1339103).

2021100001 is a wasteful number, since it uses less digits than its factorization.

2021100001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1339102.

The product of its (nonzero) digits is 4, while the sum is 7.

The square root of 2021100001 is about 44956.6457934753. The cubic root of 2021100001 is about 1264.3362817753.

Adding to 2021100001 its reverse (1000011202), we get a palindrome (3021111203).

The spelling of 2021100001 in words is "two billion, twenty-one million, one hundred thousand, one".