2021081 has 2 divisors, whose sum is σ = 2021082. Its totient is φ = 2021080.

The previous prime is 2021077. The next prime is 2021083. The reversal of 2021081 is 1801202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1915456 + 105625 = 1384^2 + 325^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021081 - 2² = 2021077 is a prime.

It is a super-2 number, since 2×2021081² = 8169536817122, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 2021083, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a nialpdrome in base 8.

It is not a weakly prime, because it can be changed into another prime (2021083) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010540 + 1010541.

It is an arithmetic number, because the mean of its divisors is an integer number (1010541).

2^2021081 is an apocalyptic number.

It is an amenable number.

2021081 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021081 is an equidigital number, since it uses as much as digits as its factorization.

2021081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 2021081 is about 1421.6472839632. The cubic root of 2021081 is about 126.4332319621.

Adding to 2021081 its reverse (1801202), we get a palindrome (3822283).

The spelling of 2021081 in words is "two million, twenty-one thousand, eighty-one".