13638618 has 96 divisors (see below), whose sum is σ = 37040640. Its totient is φ = 3674160.

The previous prime is 13638593. The next prime is 13638623. The reversal of 13638618 is 81683631.

13638618 is a `hidden beast` number, since 1 + 3 + 6 + 38 + 618 = 666.

13638618 is digitally balanced in base 2, base 4 and base 8, because in such bases it contains all the possibile digits an equal number of times.

13638618 is strictly pandigital in base 8.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 64533 + ... + 64743.

It is an arithmetic number, because the mean of its divisors is an integer number (385840).

Almost surely, 2^13638618 is an apocalyptic number.

13638618 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 13638618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18520320).

13638618 is an abundant number, since it is smaller than the sum of its proper divisors (23402022).

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

13638618 is a wasteful number, since it uses less digits than its factorization.

13638618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254 (or 242 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 13638618 is about 3693.0499590447. The cubic root of 13638618 is about 238.9223559226.

The spelling of 13638618 in words is "thirteen million, six hundred thirty-eight thousand, six hundred eighteen".