216538873 has 2 divisors, whose sum is σ = 216538874. Its totient is φ = 216538872.

The previous prime is 216538871. The next prime is 216538891. The reversal of 216538873 is 378835612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 214681104 + 1857769 = 14652^2 + 1363^2 .

It is a cyclic number.

It is not a de Polignac number, because 216538873 - 2¹ = 216538871 is a prime.

It is a super-2 number, since 2×216538873² = 93778167040220258, which contains 22 as substring.

Together with 216538871, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (216538871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108269436 + 108269437.

It is an arithmetic number, because the mean of its divisors is an integer number (108269437).

Almost surely, 2^216538873 is an apocalyptic number.

It is an amenable number.

216538873 is a deficient number, since it is larger than the sum of its proper divisors (1).

216538873 is an equidigital number, since it uses as much as digits as its factorization.

216538873 is an evil number, because the sum of its binary digits is even.

The product of its digits is 241920, while the sum is 43.

The square root of 216538873 is about 14715.2598685854. The cubic root of 216538873 is about 600.4985421263.

The spelling of 216538873 in words is "two hundred sixteen million, five hundred thirty-eight thousand, eight hundred seventy-three".