216984939 has 4 divisors (see below), whose sum is σ = 289313256. Its totient is φ = 144656624.

The previous prime is 216984919. The next prime is 216985001. The reversal of 216984939 is 939489612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 216984939 - 2⁵ = 216984907 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 216984891 and 216984900.

It is not an unprimeable number, because it can be changed into a prime (216984919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36164154 + ... + 36164159.

It is an arithmetic number, because the mean of its divisors is an integer number (72328314).

Almost surely, 2^216984939 is an apocalyptic number.

216984939 is a deficient number, since it is larger than the sum of its proper divisors (72328317).

216984939 is an equidigital number, since it uses as much as digits as its factorization.

216984939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72328316.

The product of its digits is 839808, while the sum is 51.

The square root of 216984939 is about 14730.4086501359. The cubic root of 216984939 is about 600.9105978756.

The spelling of 216984939 in words is "two hundred sixteen million, nine hundred eighty-four thousand, nine hundred thirty-nine".