2221391 has 2 divisors, whose sum is σ = 2221392. Its totient is φ = 2221390.

The previous prime is 2221381. The next prime is 2221399. The reversal of 2221391 is 1931222.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2221391 - 2¹⁰ = 2220367 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2221399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1110695 + 1110696.

It is an arithmetic number, because the mean of its divisors is an integer number (1110696).

2^2221391 is an apocalyptic number.

2221391 is a deficient number, since it is larger than the sum of its proper divisors (1).

2221391 is an equidigital number, since it uses as much as digits as its factorization.

2221391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 216, while the sum is 20.

The square root of 2221391 is about 1490.4331585147. The cubic root of 2221391 is about 130.4793153850.

The spelling of 2221391 in words is "two million, two hundred twenty-one thousand, three hundred ninety-one".