216566041 has 2 divisors, whose sum is σ = 216566042. Its totient is φ = 216566040.

The previous prime is 216566039. The next prime is 216566081. The reversal of 216566041 is 140665612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 212139225 + 4426816 = 14565^2 + 2104^2 .

It is a cyclic number.

It is not a de Polignac number, because 216566041 - 2¹ = 216566039 is a prime.

It is a super-2 number, since 2×216566041² = 93801700228827362, which contains 22 as substring.

Together with 216566039, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 216565994 and 216566012.

It is not a weakly prime, because it can be changed into another prime (216566011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108283020 + 108283021.

It is an arithmetic number, because the mean of its divisors is an integer number (108283021).

Almost surely, 2^216566041 is an apocalyptic number.

It is an amenable number.

216566041 is a deficient number, since it is larger than the sum of its proper divisors (1).

216566041 is an equidigital number, since it uses as much as digits as its factorization.

216566041 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 216566041 is about 14716.1829629833. The cubic root of 216566041 is about 600.5236548800.

The spelling of 216566041 in words is "two hundred sixteen million, five hundred sixty-six thousand, forty-one".