216019851 has 4 divisors (see below), whose sum is σ = 288026472. Its totient is φ = 144013232.

The previous prime is 216019829. The next prime is 216019861. The reversal of 216019851 is 158910612.

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 216019851 - 2⁹ = 216019339 is a prime.

It is not an unprimeable number, because it can be changed into a prime (216019861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36003306 + ... + 36003311.

It is an arithmetic number, because the mean of its divisors is an integer number (72006618).

Almost surely, 2^216019851 is an apocalyptic number.

216019851 is a deficient number, since it is larger than the sum of its proper divisors (72006621).

216019851 is an equidigital number, since it uses as much as digits as its factorization.

216019851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72006620.

The product of its (nonzero) digits is 4320, while the sum is 33.

The square root of 216019851 is about 14697.6137859178. The cubic root of 216019851 is about 600.0183799925.

The spelling of 216019851 in words is "two hundred sixteen million, nineteen thousand, eight hundred fifty-one".