9999555 has 8 divisors (see below), whose sum is σ = 15999312. Its totient is φ = 5333088.

The previous prime is 9999533. The next prime is 9999593. The reversal of 9999555 is 5559999.

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

It is not a de Polignac number, because 9999555 - 2⁸ = 9999299 is a prime.

It is a super-2 number, since 2×9999555² = 199982200396050, which contains 22 as substring.

9999555 is a lucky number.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 9999498 and 9999507.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 333304 + ... + 333333.

It is an arithmetic number, because the mean of its divisors is an integer number (1999914).

Almost surely, 2^9999555 is an apocalyptic number.

9999555 is a deficient number, since it is larger than the sum of its proper divisors (5999757).

9999555 is a wasteful number, since it uses less digits than its factorization.

9999555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 666645.

The product of its digits is 820125, while the sum is 51.

The square root of 9999555 is about 3162.2072987077. The cubic root of 9999555 is about 215.4402732110.

The spelling of 9999555 in words is "nine million, nine hundred ninety-nine thousand, five hundred fifty-five".