18309489 has 8 divisors (see below), whose sum is σ = 26632032. Its totient is φ = 11096640.

The previous prime is 18309479. The next prime is 18309491. The reversal of 18309489 is 98490381.

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

It is not a de Polignac number, because 18309489 - 2⁵ = 18309457 is a prime.

It is a super-2 number, since 2×18309489² = 670474774882242, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18309489.

It is not an unprimeable number, because it can be changed into a prime (18309439) 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, 277384 + ... + 277449.

It is an arithmetic number, because the mean of its divisors is an integer number (3329004).

Almost surely, 2^18309489 is an apocalyptic number.

It is an amenable number.

18309489 is a deficient number, since it is larger than the sum of its proper divisors (8322543).

18309489 is a wasteful number, since it uses less digits than its factorization.

18309489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 554847.

The product of its (nonzero) digits is 62208, while the sum is 42.

The square root of 18309489 is about 4278.9588686969. The cubic root of 18309489 is about 263.5676319188.

The spelling of 18309489 in words is "eighteen million, three hundred nine thousand, four hundred eighty-nine".