2147021 has 2 divisors, whose sum is σ = 2147022. Its totient is φ = 2147020.

The previous prime is 2147009. The next prime is 2147023. The reversal of 2147021 is 1207412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2102500 + 44521 = 1450^2 + 211^2 .

It is a cyclic number.

It is not a de Polignac number, because 2147021 - 2¹⁸ = 1884877 is a prime.

Together with 2147023, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2147023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1073510 + 1073511.

It is an arithmetic number, because the mean of its divisors is an integer number (1073511).

2^2147021 is an apocalyptic number.

It is an amenable number.

2147021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2147021 is an equidigital number, since it uses as much as digits as its factorization.

2147021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 112, while the sum is 17.

The square root of 2147021 is about 1465.2716471699. The cubic root of 2147021 is about 129.0066498986.

The spelling of 2147021 in words is "two million, one hundred forty-seven thousand, twenty-one".