4187021 has 2 divisors, whose sum is σ = 4187022. Its totient is φ = 4187020.

The previous prime is 4187009. The next prime is 4187023. The reversal of 4187021 is 1207814.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4141225 + 45796 = 2035^2 + 214^2 .

It is a cyclic number.

It is not a de Polignac number, because 4187021 - 2¹⁰ = 4185997 is a prime.

It is a super-2 number, since 2×4187021² = 35062289708882, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 4187023, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4187023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2093510 + 2093511.

It is an arithmetic number, because the mean of its divisors is an integer number (2093511).

Almost surely, 2^4187021 is an apocalyptic number.

It is an amenable number.

4187021 is a deficient number, since it is larger than the sum of its proper divisors (1).

4187021 is an equidigital number, since it uses as much as digits as its factorization.

4187021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 4187021 is about 2046.2211512933. The cubic root of 4187021 is about 161.1764971574.

The spelling of 4187021 in words is "four million, one hundred eighty-seven thousand, twenty-one".