16610661 has 12 divisors (see below), whose sum is σ = 24206988. Its totient is φ = 10975104.

The previous prime is 16610653. The next prime is 16610747. The reversal of 16610661 is 16601661.

It can be written as a sum of positive squares in 2 ways, for example, as 690561 + 15920100 = 831^2 + 3990^2 .

It is not a de Polignac number, because 16610661 - 2³ = 16610653 is a prime.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16610611) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7150 + ... + 9183.

It is an arithmetic number, because the mean of its divisors is an integer number (2017249).

Almost surely, 2^16610661 is an apocalyptic number.

It is an amenable number.

16610661 is a deficient number, since it is larger than the sum of its proper divisors (7596327).

16610661 is a wasteful number, since it uses less digits than its factorization.

16610661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16452 (or 16449 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 16610661 is about 4075.6178672687. The cubic root of 16610661 is about 255.1500385763.

It can be divided in two parts, 16610 and 661, that added together give a palindrome (17271).

The spelling of 16610661 in words is "sixteen million, six hundred ten thousand, six hundred sixty-one".