999031660 has 72 divisors (see below), whose sum is σ = 2345449680. Its totient is φ = 357075840.

The previous prime is 999031651. The next prime is 999031661. The reversal of 999031660 is 66130999.

It is a super-3 number, since 3×999031660³ (a number of 28 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999031661) 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, 139282 + ... + 146278.

It is an arithmetic number, because the mean of its divisors is an integer number (32575690).

Almost surely, 2^999031660 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 999031660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1172724840).

999031660 is an abundant number, since it is smaller than the sum of its proper divisors (1346418020).

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

999031660 is a wasteful number, since it uses less digits than its factorization.

999031660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7087 (or 7074 counting only the distinct ones).

The product of its (nonzero) digits is 78732, while the sum is 43.

The square root of 999031660 is about 31607.4620936259. The cubic root of 999031660 is about 999.6771157570.

The spelling of 999031660 in words is "nine hundred ninety-nine million, thirty-one thousand, six hundred sixty".