216539930 has 8 divisors (see below), whose sum is σ = 389771892. Its totient is φ = 86615968.

The previous prime is 216539923. The next prime is 216539933. The reversal of 216539930 is 39935612.

It can be written as a sum of positive squares in 2 ways, for example, as 201384481 + 15155449 = 14191^2 + 3893^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (216539933) 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, 10826987 + ... + 10827006.

Almost surely, 2^216539930 is an apocalyptic number.

216539930 is a deficient number, since it is larger than the sum of its proper divisors (173231962).

216539930 is a wasteful number, since it uses less digits than its factorization.

216539930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21654000.

The product of its (nonzero) digits is 43740, while the sum is 38.

The square root of 216539930 is about 14715.2957836396. The cubic root of 216539930 is about 600.4995192041.

The spelling of 216539930 in words is "two hundred sixteen million, five hundred thirty-nine thousand, nine hundred thirty".