16552661 has 4 divisors (see below), whose sum is σ = 16569324. Its totient is φ = 16536000.

The previous prime is 16552651. The next prime is 16552681. The reversal of 16552661 is 16625561.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13645636 + 2907025 = 3694^2 + 1705^2 .

It is a cyclic number.

It is not a de Polignac number, because 16552661 - 2⁶ = 16552597 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16552651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6740 + ... + 8861.

It is an arithmetic number, because the mean of its divisors is an integer number (4142331).

Almost surely, 2^16552661 is an apocalyptic number.

It is an amenable number.

16552661 is a deficient number, since it is larger than the sum of its proper divisors (16663).

16552661 is a wasteful number, since it uses less digits than its factorization.

16552661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16662.

The product of its digits is 10800, while the sum is 32.

The square root of 16552661 is about 4068.4961595164. The cubic root of 16552661 is about 254.8527202837.

Subtracting 16552661 from its reverse (16625561), we obtain a square (72900 = 270²).

The spelling of 16552661 in words is "sixteen million, five hundred fifty-two thousand, six hundred sixty-one".