18985538 has 16 divisors (see below), whose sum is σ = 33457536. Its totient is φ = 7965840.

The previous prime is 18985537. The next prime is 18985543. The reversal of 18985538 is 83558981.

It is a junction number, because it is equal to n+sod(n) for n = 18985492 and 18985501.

It is not an unprimeable number, because it can be changed into a prime (18985531) 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, 32906 + ... + 33477.

It is an arithmetic number, because the mean of its divisors is an integer number (2091096).

Almost surely, 2^18985538 is an apocalyptic number.

18985538 is a deficient number, since it is larger than the sum of its proper divisors (14471998).

18985538 is a wasteful number, since it uses less digits than its factorization.

18985538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66409.

The product of its digits is 345600, while the sum is 47.

The square root of 18985538 is about 4357.2397225767. The cubic root of 18985538 is about 266.7724451881.

The spelling of 18985538 in words is "eighteen million, nine hundred eighty-five thousand, five hundred thirty-eight".