16654021 has 4 divisors (see below), whose sum is σ = 16670752. Its totient is φ = 16637292.

The previous prime is 16654009. The next prime is 16654039. The reversal of 16654021 is 12045661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 16654021 - 2⁷ = 16653893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16654321) 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, 6771 + ... + 8896.

It is an arithmetic number, because the mean of its divisors is an integer number (4167688).

Almost surely, 2^16654021 is an apocalyptic number.

It is an amenable number.

16654021 is a deficient number, since it is larger than the sum of its proper divisors (16731).

16654021 is a wasteful number, since it uses less digits than its factorization.

16654021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16730.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 16654021 is about 4080.9338392089. The cubic root of 16654021 is about 255.3718578276.

Adding to 16654021 its reverse (12045661), we get a palindrome (28699682).

The spelling of 16654021 in words is "sixteen million, six hundred fifty-four thousand, twenty-one".