216243508 has 12 divisors (see below), whose sum is σ = 407535940. Its totient is φ = 99804672.

The previous prime is 216243487. The next prime is 216243527. The reversal of 216243508 is 805342612.

It can be written as a sum of positive squares in 2 ways, for example, as 97259044 + 118984464 = 9862^2 + 10908^2 .

It is a super-2 number, since 2×216243508² = 93522509504292128, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 216243508.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2079213 + ... + 2079316.

Almost surely, 2^216243508 is an apocalyptic number.

It is an amenable number.

216243508 is a deficient number, since it is larger than the sum of its proper divisors (191292432).

216243508 is a wasteful number, since it uses less digits than its factorization.

216243508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4158546 (or 4158544 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 216243508 is about 14705.2204335739. The cubic root of 216243508 is about 600.2253856952.

The spelling of 216243508 in words is "two hundred sixteen million, two hundred forty-three thousand, five hundred eight".