16399656 has 96 divisors (see below), whose sum is σ = 54687360. Its totient is φ = 4323456.

The previous prime is 16399619. The next prime is 16399661. The reversal of 16399656 is 65699361.

16399656 is a `hidden beast` number, since 1 + 639 + 9 + 6 + 5 + 6 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5301 + ... + 7803.

It is an arithmetic number, because the mean of its divisors is an integer number (569660).

Almost surely, 2^16399656 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 16399656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27343680).

16399656 is an abundant number, since it is smaller than the sum of its proper divisors (38287704).

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

16399656 is a wasteful number, since it uses less digits than its factorization.

16399656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2535 (or 2528 counting only the distinct ones).

The product of its digits is 262440, while the sum is 45.

The square root of 16399656 is about 4049.6488736679. The cubic root of 16399656 is about 254.0650421399.

The spelling of 16399656 in words is "sixteen million, three hundred ninety-nine thousand, six hundred fifty-six".