216885840 has 40 divisors (see below), whose sum is σ = 672346848. Its totient is φ = 57836160.

The previous prime is 216885821. The next prime is 216885853. The reversal of 216885840 is 48588612.

216885840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 216885792 and 216885801.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 451606 + ... + 452085.

Almost surely, 2^216885840 is an apocalyptic number.

216885840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216885840 is an abundant number, since it is smaller than the sum of its proper divisors (455461008).

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

216885840 is a wasteful number, since it uses less digits than its factorization.

216885840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 903707 (or 903701 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 42.

The square root of 216885840 is about 14727.0445100163. The cubic root of 216885840 is about 600.8191034958.

The spelling of 216885840 in words is "two hundred sixteen million, eight hundred eighty-five thousand, eight hundred forty".