16640004 has 12 divisors (see below), whose sum is σ = 38826704. Its totient is φ = 5546664.

The previous prime is 16640003. The next prime is 16640023. The reversal of 16640004 is 40004661.

16640004 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (16640003) 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, 693322 + ... + 693345.

Almost surely, 2^16640004 is an apocalyptic number.

It is an amenable number.

16640004 is an abundant number, since it is smaller than the sum of its proper divisors (22186700).

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

16640004 is a wasteful number, since it uses less digits than its factorization.

16640004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1386674 (or 1386672 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 16640004 is about 4079.2161011645. The cubic root of 16640004 is about 255.3001924111.

Adding to 16640004 its reverse (40004661), we get a palindrome (56644665).

The spelling of 16640004 in words is "sixteen million, six hundred forty thousand, four".