2871221 has 2 divisors, whose sum is σ = 2871222. Its totient is φ = 2871220.

The previous prime is 2871199. The next prime is 2871227. The reversal of 2871221 is 1221782.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2686321 + 184900 = 1639^2 + 430^2 .

It is a cyclic number.

It is not a de Polignac number, because 2871221 - 2¹⁴ = 2854837 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2871227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1435610 + 1435611.

It is an arithmetic number, because the mean of its divisors is an integer number (1435611).

2^2871221 is an apocalyptic number.

It is an amenable number.

2871221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2871221 is an equidigital number, since it uses as much as digits as its factorization.

2871221 is an odious number, because the sum of its binary digits is odd.

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

The square root of 2871221 is about 1694.4677630454. The cubic root of 2871221 is about 142.1310203810.

The spelling of 2871221 in words is "two million, eight hundred seventy-one thousand, two hundred twenty-one".