16211661 has 8 divisors (see below), whose sum is σ = 22199904. Its totient is φ = 10515600.

The previous prime is 16211653. The next prime is 16211683. The reversal of 16211661 is 16611261.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 16211661 - 2³ = 16211653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16211641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72915 + ... + 73136.

It is an arithmetic number, because the mean of its divisors is an integer number (2774988).

Almost surely, 2^16211661 is an apocalyptic number.

It is an amenable number.

16211661 is a deficient number, since it is larger than the sum of its proper divisors (5988243).

16211661 is a wasteful number, since it uses less digits than its factorization.

16211661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146091.

The product of its digits is 432, while the sum is 24.

The square root of 16211661 is about 4026.3706982840. The cubic root of 16211661 is about 253.0904965621.

The spelling of 16211661 in words is "sixteen million, two hundred eleven thousand, six hundred sixty-one".