216871189 has 2 divisors, whose sum is σ = 216871190. Its totient is φ = 216871188.

The previous prime is 216871153. The next prime is 216871223. The reversal of 216871189 is 981178612.

It is a happy number.

216871189 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 203490225 + 13380964 = 14265^2 + 3658^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216871189 is a prime.

It is a super-2 number, since 2×216871189² = 94066225236547442, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216871289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108435594 + 108435595.

It is an arithmetic number, because the mean of its divisors is an integer number (108435595).

Almost surely, 2^216871189 is an apocalyptic number.

It is an amenable number.

216871189 is a deficient number, since it is larger than the sum of its proper divisors (1).

216871189 is an equidigital number, since it uses as much as digits as its factorization.

216871189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48384, while the sum is 43.

The square root of 216871189 is about 14726.5470834137. The cubic root of 216871189 is about 600.8055744139.

The spelling of 216871189 in words is "two hundred sixteen million, eight hundred seventy-one thousand, one hundred eighty-nine".