999161568 has 108 divisors (see below), whose sum is σ = 2951119080. Its totient is φ = 332983872.

The previous prime is 999161567. The next prime is 999161573. The reversal of 999161568 is 865161999.

It is a tau number, because it is divible by the number of its divisors (108).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999161567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 207573 + ... + 212331.

Almost surely, 2^999161568 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 999161568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1475559540).

999161568 is an abundant number, since it is smaller than the sum of its proper divisors (1951957512).

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

999161568 is an frugal number, since it uses more digits than its factorization.

999161568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4793 (or 4764 counting only the distinct ones).

The product of its digits is 1049760, while the sum is 54.

The square root of 999161568 is about 31609.5170478766. The cubic root of 999161568 is about 999.7204445227.

The spelling of 999161568 in words is "nine hundred ninety-nine million, one hundred sixty-one thousand, five hundred sixty-eight".