18864872 has 32 divisors (see below), whose sum is σ = 40101600. Its totient is φ = 8247744.

The previous prime is 18864871. The next prime is 18864887. The reversal of 18864872 is 27846881.

It is not an unprimeable number, because it can be changed into a prime (18864871) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2798 + ... + 6749.

It is an arithmetic number, because the mean of its divisors is an integer number (1253175).

Almost surely, 2^18864872 is an apocalyptic number.

It is an amenable number.

18864872 is an abundant number, since it is smaller than the sum of its proper divisors (21236728).

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

18864872 is a wasteful number, since it uses less digits than its factorization.

18864872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9585 (or 9581 counting only the distinct ones).

The product of its digits is 172032, while the sum is 44.

The square root of 18864872 is about 4343.3710410233. The cubic root of 18864872 is about 266.2060701766.

Subtracting 18864872 from its reverse (27846881), we obtain a square (8982009 = 2997²).

The spelling of 18864872 in words is "eighteen million, eight hundred sixty-four thousand, eight hundred seventy-two".