2021001001 has 2 divisors, whose sum is σ = 2021001002. Its totient is φ = 2021001000.

The previous prime is 2021000999. The next prime is 2021001041. The reversal of 2021001001 is 1001001202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2007488025 + 13512976 = 44805^2 + 3676^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021001001 - 2¹ = 2021000999 is a prime.

Together with 2021000999, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (2021001041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010500500 + 1010500501.

It is an arithmetic number, because the mean of its divisors is an integer number (1010500501).

Almost surely, 2^2021001001 is an apocalyptic number.

It is an amenable number.

2021001001 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021001001 is an equidigital number, since it uses as much as digits as its factorization.

2021001001 is an odious number, because the sum of its binary digits is odd.

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

The square root of 2021001001 is about 44955.5447192001. The cubic root of 2021001001 is about 1264.3156376813.

Adding to 2021001001 its reverse (1001001202), we get a palindrome (3022002203).

It can be divided in two parts, 202 and 1001001, that multiplied together give a palindrome (202202202).

The spelling of 2021001001 in words is "two billion, twenty-one million, one thousand, one".