216188878161 has 64 divisors (see below), whose sum is σ = 319806662400. Its totient is φ = 129409532928.

The previous prime is 216188878153. The next prime is 216188878193. The reversal of 216188878161 is 161878881612.

It is not a de Polignac number, because 216188878161 - 2³ = 216188878153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (216188878111) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 136914270 + ... + 136915848.

It is an arithmetic number, because the mean of its divisors is an integer number (4996979100).

Almost surely, 2^216188878161 is an apocalyptic number.

It is an amenable number.

216188878161 is a deficient number, since it is larger than the sum of its proper divisors (103617784239).

216188878161 is an equidigital number, since it uses as much as digits as its factorization.

216188878161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1763 (or 1689 counting only the distinct ones).

The product of its digits is 2064384, while the sum is 57.

The spelling of 216188878161 in words is "two hundred sixteen billion, one hundred eighty-eight million, eight hundred seventy-eight thousand, one hundred sixty-one".