999712224 has 144 divisors (see below), whose sum is σ = 3294057312. Its totient is φ = 281677824.

The previous prime is 999712199. The next prime is 999712229. The reversal of 999712224 is 422217999.

It is a tau number, because it is divible by the number of its divisors (144).

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

It is a self number, because there is not a number n which added to its sum of digits gives 999712224.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999712229) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 143772 + ... + 150564.

It is an arithmetic number, because the mean of its divisors is an integer number (22875398).

Almost surely, 2^999712224 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 999712224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1647028656).

999712224 is an abundant number, since it is smaller than the sum of its proper divisors (2294345088).

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

999712224 is a wasteful number, since it uses less digits than its factorization.

999712224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6889 (or 6878 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 999712224 is about 31618.2261362019. The cubic root of 999712224 is about 999.9040654635.

The spelling of 999712224 in words is "nine hundred ninety-nine million, seven hundred twelve thousand, two hundred twenty-four".