216305644 has 12 divisors (see below), whose sum is σ = 378653968. Its totient is φ = 108118800.

The previous prime is 216305641. The next prime is 216305657. The reversal of 216305644 is 446503612.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (216305641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10534 + ... + 23314.

Almost surely, 2^216305644 is an apocalyptic number.

It is an amenable number.

216305644 is a deficient number, since it is larger than the sum of its proper divisors (162348324).

216305644 is a wasteful number, since it uses less digits than its factorization.

216305644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17016 (or 17014 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 216305644 is about 14707.3330009217. Note that the first 3 decimals coincide. The cubic root of 216305644 is about 600.2828703234.

The spelling of 216305644 in words is "two hundred sixteen million, three hundred five thousand, six hundred forty-four".