999998855 has 8 divisors (see below), whose sum is σ = 1201271472. Its totient is φ = 799150528.

The previous prime is 999998843. The next prime is 999998863. The reversal of 999998855 is 558899999.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 999998855 - 2¹⁴ = 999982471 is a prime.

It is a super-2 number, since 2×999998855² = 1999995420002622050, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 100862 + ... + 110331.

It is an arithmetic number, because the mean of its divisors is an integer number (150158934).

Almost surely, 2^999998855 is an apocalyptic number.

999998855 is a deficient number, since it is larger than the sum of its proper divisors (201272617).

999998855 is a wasteful number, since it uses less digits than its factorization.

999998855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212145.

The product of its digits is 94478400, while the sum is 71.

The square root of 999998855 is about 31622.7584976390. The cubic root of 999998855 is about 999.9996183332. Note that the first 3 decimals are identical.

The spelling of 999998855 in words is "nine hundred ninety-nine million, nine hundred ninety-eight thousand, eight hundred fifty-five".