16642663 has 4 divisors (see below), whose sum is σ = 16659808. Its totient is φ = 16625520.

The previous prime is 16642631. The next prime is 16642667. The reversal of 16642663 is 36624661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36624661 = 941 ⋅38921.

It is a cyclic number.

It is not a de Polignac number, because 16642663 - 2⁵ = 16642631 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 (16642667) 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 3 ways as a sum of consecutive naturals, for example, 7023 + ... + 9088.

It is an arithmetic number, because the mean of its divisors is an integer number (4164952).

Almost surely, 2^16642663 is an apocalyptic number.

16642663 is a deficient number, since it is larger than the sum of its proper divisors (17145).

16642663 is a wasteful number, since it uses less digits than its factorization.

16642663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17144.

The product of its digits is 31104, while the sum is 34.

The square root of 16642663 is about 4079.5420086083. The cubic root of 16642663 is about 255.3137903056.

The spelling of 16642663 in words is "sixteen million, six hundred forty-two thousand, six hundred sixty-three".