18268720 has 20 divisors (see below), whose sum is σ = 42474960. Its totient is φ = 7307456.

The previous prime is 18268711. The next prime is 18268721. The reversal of 18268720 is 2786281.

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×18268720² = 667492260876800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18268721) 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, 114100 + ... + 114259.

It is an arithmetic number, because the mean of its divisors is an integer number (2123748).

Almost surely, 2^18268720 is an apocalyptic number.

18268720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18268720 is an abundant number, since it is smaller than the sum of its proper divisors (24206240).

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

18268720 is a wasteful number, since it uses less digits than its factorization.

18268720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 228372 (or 228366 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 34.

The square root of 18268720 is about 4274.1923213632. The cubic root of 18268720 is about 263.3718614068.

The spelling of 18268720 in words is "eighteen million, two hundred sixty-eight thousand, seven hundred twenty".