216471906 has 96 divisors (see below), whose sum is σ = 584081280. Its totient is φ = 59143392.

The previous prime is 216471851. The next prime is 216471911. The reversal of 216471906 is 609174612.

216471906 is a `hidden beast` number, since 2 + 1 + 647 + 1 + 9 + 0 + 6 = 666.

216471906 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 59080 + ... + 62636.

It is an arithmetic number, because the mean of its divisors is an integer number (6084180).

Almost surely, 2^216471906 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216471906, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (292040640).

216471906 is an abundant number, since it is smaller than the sum of its proper divisors (367609374).

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

216471906 is a wasteful number, since it uses less digits than its factorization.

216471906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3605 (or 3592 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 216471906 is about 14712.9842656070. The cubic root of 216471906 is about 600.4366321768.

The spelling of 216471906 in words is "two hundred sixteen million, four hundred seventy-one thousand, nine hundred six".