213123099999 has 4 divisors (see below), whose sum is σ = 284164133336. Its totient is φ = 142082066664.

The previous prime is 213123099991. The next prime is 213123100007. The reversal of 213123099999 is 999990321312.

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 (213123099991) and next prime (213123100007).

It is not a de Polignac number, because 213123099999 - 2³ = 213123099991 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 (213123099991) 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, 35520516664 + ... + 35520516669.

It is an arithmetic number, because the mean of its divisors is an integer number (71041033334).

Almost surely, 2^213123099999 is an apocalyptic number.

213123099999 is a deficient number, since it is larger than the sum of its proper divisors (71041033337).

213123099999 is an equidigital number, since it uses as much as digits as its factorization.

213123099999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71041033336.

The product of its (nonzero) digits is 2125764, while the sum is 57.

The spelling of 213123099999 in words is "two hundred thirteen billion, one hundred twenty-three million, ninety-nine thousand, nine hundred ninety-nine".