18728969 has 8 divisors (see below), whose sum is σ = 22335360. Its totient is φ = 15355296.

The previous prime is 18728921. The next prime is 18728977. The reversal of 18728969 is 96982781.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18728969 is a prime.

It is a super-2 number, since 2×18728969² = 701548559605922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18728069) 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, 58004 + ... + 58325.

It is an arithmetic number, because the mean of its divisors is an integer number (2791920).

Almost surely, 2^18728969 is an apocalyptic number.

It is an amenable number.

18728969 is a deficient number, since it is larger than the sum of its proper divisors (3606391).

18728969 is a wasteful number, since it uses less digits than its factorization.

18728969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116359.

The product of its digits is 435456, while the sum is 50.

The square root of 18728969 is about 4327.6978868678. The cubic root of 18728969 is about 265.5652772582.

The spelling of 18728969 in words is "eighteen million, seven hundred twenty-eight thousand, nine hundred sixty-nine".