216707399 has 4 divisors (see below), whose sum is σ = 217332264. Its totient is φ = 216082536.

The previous prime is 216707389. The next prime is 216707411. The reversal of 216707399 is 993707612.

It is a happy number.

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 216707399 - 2²⁰ = 215658823 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216707389) 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, 311912 + ... + 312605.

It is an arithmetic number, because the mean of its divisors is an integer number (54333066).

Almost surely, 2^216707399 is an apocalyptic number.

216707399 is a deficient number, since it is larger than the sum of its proper divisors (624865).

216707399 is an equidigital number, since it uses as much as digits as its factorization.

216707399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 624864.

The product of its (nonzero) digits is 142884, while the sum is 44.

The square root of 216707399 is about 14720.9849874253. The cubic root of 216707399 is about 600.6542853326.

The spelling of 216707399 in words is "two hundred sixteen million, seven hundred seven thousand, three hundred ninety-nine".