16638642 has 32 divisors (see below), whose sum is σ = 38923200. Its totient is φ = 5253984.

The previous prime is 16638619. The next prime is 16638647. The reversal of 16638642 is 24683661.

16638642 is a `hidden beast` number, since 1 + 6 + 6 + 3 + 8 + 642 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 16638597 and 16638606.

It is not an unprimeable number, because it can be changed into a prime (16638647) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7083 + ... + 9134.

It is an arithmetic number, because the mean of its divisors is an integer number (1216350).

Almost surely, 2^16638642 is an apocalyptic number.

16638642 is an abundant number, since it is smaller than the sum of its proper divisors (22284558).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16638642 is a wasteful number, since it uses less digits than its factorization.

16638642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16247 (or 16241 counting only the distinct ones).

The product of its digits is 41472, while the sum is 36.

The square root of 16638642 is about 4079.0491539083. The cubic root of 16638642 is about 255.2932267007.

The spelling of 16638642 in words is "sixteen million, six hundred thirty-eight thousand, six hundred forty-two".