16638004 has 6 divisors (see below), whose sum is σ = 29116514. Its totient is φ = 8319000.

The previous prime is 16638001. The next prime is 16638023. The reversal of 16638004 is 40083661.

It can be written as a sum of positive squares in only one way, i.e., 11209104 + 5428900 = 3348^2 + 2330^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16638001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2079747 + ... + 2079754.

Almost surely, 2^16638004 is an apocalyptic number.

It is an amenable number.

16638004 is a deficient number, since it is larger than the sum of its proper divisors (12478510).

16638004 is a wasteful number, since it uses less digits than its factorization.

16638004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4159505 (or 4159503 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 16638004 is about 4078.9709486585. The cubic root of 16638004 is about 255.2899636307.

The spelling of 16638004 in words is "sixteen million, six hundred thirty-eight thousand, four".