999856837118 has 4 divisors (see below), whose sum is σ = 1499785255680. Its totient is φ = 499928418558.

The previous prime is 999856837117. The next prime is 999856837123. The reversal of 999856837118 is 811738658999.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 811738658999 = 163 ⋅4979991773.

It is a super-2 number, since 2×999856837118² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999856837117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249964209278 + ... + 249964209281.

It is an arithmetic number, because the mean of its divisors is an integer number (374946313920).

Almost surely, 2^999856837118 is an apocalyptic number.

999856837118 is a deficient number, since it is larger than the sum of its proper divisors (499928418562).

999856837118 is a wasteful number, since it uses less digits than its factorization.

999856837118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499928418561.

The product of its digits is 235146240, while the sum is 74.

The spelling of 999856837118 in words is "nine hundred ninety-nine billion, eight hundred fifty-six million, eight hundred thirty-seven thousand, one hundred eighteen".