216702561 has 16 divisors (see below), whose sum is σ = 295213248. Its totient is φ = 141355200.

The previous prime is 216702557. The next prime is 216702569. The reversal of 216702561 is 165207612.

It is not a de Polignac number, because 216702561 - 2² = 216702557 is a prime.

It is not an unprimeable number, because it can be changed into a prime (216702569) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33046 + ... + 39056.

It is an arithmetic number, because the mean of its divisors is an integer number (18450828).

Almost surely, 2^216702561 is an apocalyptic number.

It is an amenable number.

216702561 is a deficient number, since it is larger than the sum of its proper divisors (78510687).

216702561 is a wasteful number, since it uses less digits than its factorization.

216702561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6272.

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 216702561 is about 14720.8206632647. The cubic root of 216702561 is about 600.6498154236.

The spelling of 216702561 in words is "two hundred sixteen million, seven hundred two thousand, five hundred sixty-one".