209916459023 has 4 divisors (see below), whose sum is σ = 217154957640. Its totient is φ = 202677960408.

The previous prime is 209916458989. The next prime is 209916459061. The reversal of 209916459023 is 320954619902.

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 209916459023 - 2¹⁴ = 209916442639 is a prime.

It is a super-2 number, since 2×209916459023² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209916459523) 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, 3619249265 + ... + 3619249322.

It is an arithmetic number, because the mean of its divisors is an integer number (54288739410).

Almost surely, 2^209916459023 is an apocalyptic number.

209916459023 is a deficient number, since it is larger than the sum of its proper divisors (7238498617).

209916459023 is an equidigital number, since it uses as much as digits as its factorization.

209916459023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7238498616.

The product of its (nonzero) digits is 1049760, while the sum is 50.

The spelling of 209916459023 in words is "two hundred nine billion, nine hundred sixteen million, four hundred fifty-nine thousand, twenty-three".