18720004 has 6 divisors (see below), whose sum is σ = 32760014. Its totient is φ = 9360000.

The previous prime is 18719983. The next prime is 18720083. The reversal of 18720004 is 40002781.

It can be written as a sum of positive squares in only one way, i.e., 16892100 + 1827904 = 4110^2 + 1352^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2339997 + ... + 2340004.

Almost surely, 2^18720004 is an apocalyptic number.

It is an amenable number.

18720004 is a deficient number, since it is larger than the sum of its proper divisors (14040010).

18720004 is a wasteful number, since it uses less digits than its factorization.

18720004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4680005 (or 4680003 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 18720004 is about 4326.6619928069. The cubic root of 18720004 is about 265.5228977642.

Adding to 18720004 its reverse (40002781), we get a palindrome (58722785).

The spelling of 18720004 in words is "eighteen million, seven hundred twenty thousand, four".