999227640 has 128 divisors (see below), whose sum is σ = 3141711360. Its totient is φ = 253761024.

The previous prime is 999227627. The next prime is 999227657. The reversal of 999227640 is 46722999.

999227640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 999227640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 763867 + ... + 765173.

It is an arithmetic number, because the mean of its divisors is an integer number (24544620).

Almost surely, 2^999227640 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 999227640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1570855680).

999227640 is an abundant number, since it is smaller than the sum of its proper divisors (2142483720).

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

999227640 is a wasteful number, since it uses less digits than its factorization.

999227640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1621 (or 1617 counting only the distinct ones).

The product of its (nonzero) digits is 489888, while the sum is 48.

The square root of 999227640 is about 31610.5621588734. The cubic root of 999227640 is about 999.7424803560.

The spelling of 999227640 in words is "nine hundred ninety-nine million, two hundred twenty-seven thousand, six hundred forty".