216218138 has 32 divisors (see below), whose sum is σ = 363528000. Its totient is φ = 95848704.

The previous prime is 216218131. The next prime is 216218143. The reversal of 216218138 is 831812612.

216218138 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (216218131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 126413 + ... + 128111.

It is an arithmetic number, because the mean of its divisors is an integer number (11360250).

Almost surely, 2^216218138 is an apocalyptic number.

216218138 is a deficient number, since it is larger than the sum of its proper divisors (147309862).

216218138 is a wasteful number, since it uses less digits than its factorization.

216218138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1934.

The product of its digits is 4608, while the sum is 32.

The square root of 216218138 is about 14704.3577894446. The cubic root of 216218138 is about 600.2019116748.

The spelling of 216218138 in words is "two hundred sixteen million, two hundred eighteen thousand, one hundred thirty-eight".