216431465 has 4 divisors (see below), whose sum is σ = 259717764. Its totient is φ = 173145168.

The previous prime is 216431461. The next prime is 216431473. The reversal of 216431465 is 564134612.

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

It can be written as a sum of positive squares in 2 ways, for example, as 27836176 + 188595289 = 5276^2 + 13733^2 .

It is a cyclic number.

It is not a de Polignac number, because 216431465 - 2² = 216431461 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216431461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21643142 + ... + 21643151.

It is an arithmetic number, because the mean of its divisors is an integer number (64929441).

Almost surely, 2^216431465 is an apocalyptic number.

It is an amenable number.

216431465 is a deficient number, since it is larger than the sum of its proper divisors (43286299).

216431465 is an equidigital number, since it uses as much as digits as its factorization.

216431465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43286298.

The product of its digits is 17280, while the sum is 32.

The square root of 216431465 is about 14711.6098711188. The cubic root of 216431465 is about 600.3992389179.

The spelling of 216431465 in words is "two hundred sixteen million, four hundred thirty-one thousand, four hundred sixty-five".