216670447 has 4 divisors (see below), whose sum is σ = 247623376. Its totient is φ = 185717520.

The previous prime is 216670417. The next prime is 216670477. The reversal of 216670447 is 744076612.

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

It is an interprime number because it is at equal distance from previous prime (216670417) and next prime (216670477).

It is a cyclic number.

It is not a de Polignac number, because 216670447 - 2¹⁹ = 216146159 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216670417) 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, 15476454 + ... + 15476467.

It is an arithmetic number, because the mean of its divisors is an integer number (61905844).

Almost surely, 2^216670447 is an apocalyptic number.

216670447 is a deficient number, since it is larger than the sum of its proper divisors (30952929).

216670447 is an equidigital number, since it uses as much as digits as its factorization.

216670447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30952928.

The product of its (nonzero) digits is 56448, while the sum is 37.

The square root of 216670447 is about 14719.7298548581. The cubic root of 216670447 is about 600.6201430760.

The spelling of 216670447 in words is "two hundred sixteen million, six hundred seventy thousand, four hundred forty-seven".