18689436 has 18 divisors (see below), whose sum is σ = 47242832. Its totient is φ = 6229800.

The previous prime is 18689431. The next prime is 18689441. The reversal of 18689436 is 63498681.

It is an interprime number because it is at equal distance from previous prime (18689431) and next prime (18689441).

It is a tau number, because it is divible by the number of its divisors (18).

It is a junction number, because it is equal to n+sod(n) for n = 18689391 and 18689400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18689431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 259540 + ... + 259611.

Almost surely, 2^18689436 is an apocalyptic number.

It is an amenable number.

18689436 is an abundant number, since it is smaller than the sum of its proper divisors (28553396).

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

18689436 is a wasteful number, since it uses less digits than its factorization.

18689436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 519161 (or 519156 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 18689436 is about 4323.1280341901. The cubic root of 18689436 is about 265.3782944159.

The spelling of 18689436 in words is "eighteen million, six hundred eighty-nine thousand, four hundred thirty-six".