999521328 has 40 divisors (see below), whose sum is σ = 2780721328. Its totient is φ = 307544832.

The previous prime is 999521321. The next prime is 999521333. The reversal of 999521328 is 823125999.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (999521321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 800275 + ... + 801522.

Almost surely, 2^999521328 is an apocalyptic number.

It is an amenable number.

999521328 is an abundant number, since it is smaller than the sum of its proper divisors (1781200000).

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

999521328 is a wasteful number, since it uses less digits than its factorization.

999521328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1601821 (or 1601815 counting only the distinct ones).

The product of its digits is 349920, while the sum is 48.

The square root of 999521328 is about 31615.2072269027. The cubic root of 999521328 is about 999.8404172014.

The spelling of 999521328 in words is "nine hundred ninety-nine million, five hundred twenty-one thousand, three hundred twenty-eight".