216685140 has 48 divisors (see below), whose sum is σ = 693393792. Its totient is φ = 49527936.

The previous prime is 216685103. The next prime is 216685163. The reversal of 216685140 is 41586612.

216685140 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 257539 + ... + 258378.

It is an arithmetic number, because the mean of its divisors is an integer number (14445704).

Almost surely, 2^216685140 is an apocalyptic number.

216685140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216685140 is an abundant number, since it is smaller than the sum of its proper divisors (476708652).

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

216685140 is a wasteful number, since it uses less digits than its factorization.

216685140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 515936 (or 515934 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 216685140 is about 14720.2289384371. The cubic root of 216685140 is about 600.6337193196.

The spelling of 216685140 in words is "two hundred sixteen million, six hundred eighty-five thousand, one hundred forty".