999661696 has 64 divisors (see below), whose sum is σ = 2267092800. Its totient is φ = 434621440.

The previous prime is 999661679. The next prime is 999661757. The reversal of 999661696 is 696166999.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16950 + ... + 47818.

It is an arithmetic number, because the mean of its divisors is an integer number (35423325).

Almost surely, 2^999661696 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 999661696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1133546400).

999661696 is an abundant number, since it is smaller than the sum of its proper divisors (1267431104).

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

999661696 is a wasteful number, since it uses less digits than its factorization.

999661696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30917 (or 30905 counting only the distinct ones).

The product of its digits is 8503056, while the sum is 61.

The square root of 999661696 is about 31617.4270932978. The cubic root of 999661696 is about 999.8872192810.

The spelling of 999661696 in words is "nine hundred ninety-nine million, six hundred sixty-one thousand, six hundred ninety-six".