216245646 has 64 divisors (see below), whose sum is σ = 501350400. Its totient is φ = 69012000.

The previous prime is 216245641. The next prime is 216245681. The reversal of 216245646 is 646542612.

216245646 is a `hidden beast` number, since 2 + 1 + 6 + 2 + 4 + 5 + 646 = 666.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 216245646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216245641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 168435 + ... + 169713.

It is an arithmetic number, because the mean of its divisors is an integer number (7833600).

Almost surely, 2^216245646 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216245646, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (250675200).

216245646 is an abundant number, since it is smaller than the sum of its proper divisors (285104754).

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

216245646 is a wasteful number, since it uses less digits than its factorization.

216245646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1422 (or 1416 counting only the distinct ones).

The product of its digits is 69120, while the sum is 36.

The square root of 216245646 is about 14705.2931286663. The cubic root of 216245646 is about 600.2273638319.

The spelling of 216245646 in words is "two hundred sixteen million, two hundred forty-five thousand, six hundred forty-six".