216543645 has 32 divisors (see below), whose sum is σ = 385632000. Its totient is φ = 115290432.

The previous prime is 216543631. The next prime is 216543659. The reversal of 216543645 is 546345612.

216543645 is a `hidden beast` number, since 2 + 1 + 6 + 5 + 4 + 3 + 645 = 666.

216543645 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (216543631) and next prime (216543659).

It is not a de Polignac number, because 216543645 - 2⁷ = 216543517 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 110131 + ... + 112079.

It is an arithmetic number, because the mean of its divisors is an integer number (12051000).

Almost surely, 2^216543645 is an apocalyptic number.

It is an amenable number.

216543645 is a deficient number, since it is larger than the sum of its proper divisors (169088355).

216543645 is a wasteful number, since it uses less digits than its factorization.

216543645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2786 (or 2780 counting only the distinct ones).

The product of its digits is 86400, while the sum is 36.

The square root of 216543645 is about 14715.4220122972. The cubic root of 216543645 is about 600.5029532789.

The spelling of 216543645 in words is "two hundred sixteen million, five hundred forty-three thousand, six hundred forty-five".