999220 has 24 divisors (see below), whose sum is σ = 2145024. Its totient is φ = 390816.

The previous prime is 999217. The next prime is 999221. The reversal of 999220 is 22999.

It is an Ulam number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 409 + ... + 1471.

It is an arithmetic number, because the mean of its divisors is an integer number (89376).

2⁹⁹⁹²²⁰ is an apocalyptic number.

It is an amenable number.

999220 is an abundant number, since it is smaller than the sum of its proper divisors (1145804).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

999220 is a wasteful number, since it uses less digits than its factorization.

999220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1119 (or 1117 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 999220 is about 999.6099239203. The cubic root of 999220 is about 99.9739932371.

The spelling of 999220 in words is "nine hundred ninety-nine thousand, two hundred twenty".