16561552 has 40 divisors (see below), whose sum is σ = 37944000. Its totient is φ = 6851712.

The previous prime is 16561549. The next prime is 16561577. The reversal of 16561552 is 25516561.

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 7 ways as a sum of consecutive naturals, for example, 699 + ... + 5797.

It is an arithmetic number, because the mean of its divisors is an integer number (948600).

Almost surely, 2^16561552 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 16561552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18972000).

16561552 is an abundant number, since it is smaller than the sum of its proper divisors (21382448).

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

16561552 is a wasteful number, since it uses less digits than its factorization.

16561552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5143 (or 5137 counting only the distinct ones).

The product of its digits is 9000, while the sum is 31.

The square root of 16561552 is about 4069.5886770041. The cubic root of 16561552 is about 254.8983421520.

The spelling of 16561552 in words is "sixteen million, five hundred sixty-one thousand, five hundred fifty-two".