18420259 has 8 divisors (see below), whose sum is σ = 21640752. Its totient is φ = 15457440.

The previous prime is 18420251. The next prime is 18420271. The reversal of 18420259 is 95202481.

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

It is a cyclic number.

It is not a de Polignac number, because 18420259 - 2³ = 18420251 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18420259.

It is not an unprimeable number, because it can be changed into a prime (18420251) 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, 64264 + ... + 64549.

It is an arithmetic number, because the mean of its divisors is an integer number (2705094).

Almost surely, 2^18420259 is an apocalyptic number.

18420259 is a deficient number, since it is larger than the sum of its proper divisors (3220493).

18420259 is a wasteful number, since it uses less digits than its factorization.

18420259 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128837.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 18420259 is about 4291.8829201179. The cubic root of 18420259 is about 264.0980801397.

The spelling of 18420259 in words is "eighteen million, four hundred twenty thousand, two hundred fifty-nine".