216863645 has 32 divisors (see below), whose sum is σ = 284135040. Its totient is φ = 158279680.

The previous prime is 216863639. The next prime is 216863671. The reversal of 216863645 is 546368612.

It is not a de Polignac number, because 216863645 - 2²⁰ = 215815069 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, 415985 + ... + 416505.

It is an arithmetic number, because the mean of its divisors is an integer number (8879220).

Almost surely, 2^216863645 is an apocalyptic number.

It is an amenable number.

216863645 is a deficient number, since it is larger than the sum of its proper divisors (67271395).

216863645 is a wasteful number, since it uses less digits than its factorization.

216863645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 685.

The product of its digits is 207360, while the sum is 41.

The square root of 216863645 is about 14726.2909451090. The cubic root of 216863645 is about 600.7986078672.

The spelling of 216863645 in words is "two hundred sixteen million, eight hundred sixty-three thousand, six hundred forty-five".