99999918213 has 32 divisors (see below), whose sum is σ = 150065104896. Its totient is φ = 58771508928.

The previous prime is 99999918169. The next prime is 99999918289. The reversal of 99999918213 is 31281999999.

It is a happy number.

It is not a de Polignac number, because 99999918213 - 2¹⁰ = 99999917189 is a prime.

It is a super-2 number, since 2×99999918213² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (69).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99999918313) 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 31 ways as a sum of consecutive naturals, for example, 494206 + ... + 666512.

It is an arithmetic number, because the mean of its divisors is an integer number (4689534528).

Almost surely, 2^99999918213 is an apocalyptic number.

It is an amenable number.

99999918213 is a deficient number, since it is larger than the sum of its proper divisors (50065186683).

99999918213 is a wasteful number, since it uses less digits than its factorization.

99999918213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172993.

The product of its digits is 25509168, while the sum is 69.

The spelling of 99999918213 in words is "ninety-nine billion, nine hundred ninety-nine million, nine hundred eighteen thousand, two hundred thirteen".