16663557 has 4 divisors (see below), whose sum is σ = 22218080. Its totient is φ = 11109036.

The previous prime is 16663541. The next prime is 16663583. The reversal of 16663557 is 75536661.

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 not a de Polignac number, because 16663557 - 2⁴ = 16663541 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 (16663657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2777257 + ... + 2777262.

It is an arithmetic number, because the mean of its divisors is an integer number (5554520).

Almost surely, 2^16663557 is an apocalyptic number.

It is an amenable number.

16663557 is a deficient number, since it is larger than the sum of its proper divisors (5554523).

16663557 is an equidigital number, since it uses as much as digits as its factorization.

16663557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5554522.

The product of its digits is 113400, while the sum is 39.

The square root of 16663557 is about 4082.1020320418. The cubic root of 16663557 is about 255.4205900304.

The spelling of 16663557 in words is "sixteen million, six hundred sixty-three thousand, five hundred fifty-seven".