216445871 has 2 divisors, whose sum is σ = 216445872. Its totient is φ = 216445870.

The previous prime is 216445841. The next prime is 216445883. The reversal of 216445871 is 178544612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 216445871 - 2¹⁰ = 216444847 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216445811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108222935 + 108222936.

It is an arithmetic number, because the mean of its divisors is an integer number (108222936).

Almost surely, 2^216445871 is an apocalyptic number.

216445871 is a deficient number, since it is larger than the sum of its proper divisors (1).

216445871 is an equidigital number, since it uses as much as digits as its factorization.

216445871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53760, while the sum is 38.

The square root of 216445871 is about 14712.0994762814. The cubic root of 216445871 is about 600.4125597775.

The spelling of 216445871 in words is "two hundred sixteen million, four hundred forty-five thousand, eight hundred seventy-one".