999648 has 96 divisors (see below), whose sum is σ = 3175200. Its totient is φ = 304128.

The previous prime is 999631. The next prime is 999653. The reversal of 999648 is 846999.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×999648² = 1998592247808, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a zygodrome in base 7.

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 999648.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11188 + ... + 11276.

It is an arithmetic number, because the mean of its divisors is an integer number (33075).

2⁹⁹⁹⁶⁴⁸ 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 999648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1587600).

999648 is an abundant number, since it is smaller than the sum of its proper divisors (2175552).

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

999648 is a wasteful number, since it uses less digits than its factorization.

999648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121 (or 107 counting only the distinct ones).

The product of its digits is 139968, while the sum is 45.

The square root of 999648 is about 999.8239845093. The cubic root of 999648 is about 99.9882652897.

The spelling of 999648 in words is "nine hundred ninety-nine thousand, six hundred forty-eight".