216189447 has 4 divisors (see below), whose sum is σ = 288252600. Its totient is φ = 144126296.

The previous prime is 216189439. The next prime is 216189487. The reversal of 216189447 is 744981612.

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 216189447 - 2³ = 216189439 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 216189399 and 216189408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216189487) 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, 36031572 + ... + 36031577.

It is an arithmetic number, because the mean of its divisors is an integer number (72063150).

Almost surely, 2^216189447 is an apocalyptic number.

216189447 is a deficient number, since it is larger than the sum of its proper divisors (72063153).

216189447 is an equidigital number, since it uses as much as digits as its factorization.

216189447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72063152.

The product of its digits is 96768, while the sum is 42.

The square root of 216189447 is about 14703.3821619381. The cubic root of 216189447 is about 600.1753626305.

The spelling of 216189447 in words is "two hundred sixteen million, one hundred eighty-nine thousand, four hundred forty-seven".