216188838 has 24 divisors (see below), whose sum is σ = 485758728. Its totient is φ = 72062784.

The previous prime is 216188831. The next prime is 216188839. The reversal of 216188838 is 838881612.

216188838 is a `hidden beast` number, since 21 + 618 + 8 + 8 + 3 + 8 = 666.

It is a super-2 number, since 2×216188838² = 93475227351580488, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 216188793 and 216188802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216188831) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 221931 + ... + 222902.

It is an arithmetic number, because the mean of its divisors is an integer number (20239947).

Almost surely, 2^216188838 is an apocalyptic number.

216188838 is an abundant number, since it is smaller than the sum of its proper divisors (269569890).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

216188838 is an equidigital number, since it uses as much as digits as its factorization.

216188838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 444850 (or 444838 counting only the distinct ones).

The product of its digits is 147456, while the sum is 45.

The square root of 216188838 is about 14703.3614524026. The cubic root of 216188838 is about 600.1747990705.

The spelling of 216188838 in words is "two hundred sixteen million, one hundred eighty-eight thousand, eight hundred thirty-eight".