999408 has 40 divisors (see below), whose sum is σ = 2642688. Its totient is φ = 325312.

The previous prime is 999389. The next prime is 999431. The reversal of 999408 is 804999.

It is a zygodrome in base 2.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 999408.

It is an unprimeable number.

999408 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2035 + ... + 2477.

2⁹⁹⁹⁴⁰⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 999408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1321344).

999408 is an abundant number, since it is smaller than the sum of its proper divisors (1643280).

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

999408 is a wasteful number, since it uses less digits than its factorization.

999408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 501 (or 495 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 39.

The square root of 999408 is about 999.7039561790. The cubic root of 999408 is about 99.9802627713.

The spelling of 999408 in words is "nine hundred ninety-nine thousand, four hundred eight".