18634518 has 48 divisors (see below), whose sum is σ = 46814976. Its totient is φ = 5246640.

The previous prime is 18634489. The next prime is 18634519. The reversal of 18634518 is 81543681.

18634518 is a `hidden beast` number, since 1 + 8 + 634 + 5 + 18 = 666.

It is a super-2 number, since 2×18634518² = 694490522184648, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18634519) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7905 + ... + 9987.

It is an arithmetic number, because the mean of its divisors is an integer number (975312).

Almost surely, 2^18634518 is an apocalyptic number.

18634518 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 18634518, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23407488).

18634518 is an abundant number, since it is smaller than the sum of its proper divisors (28180458).

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

18634518 is a wasteful number, since it uses less digits than its factorization.

18634518 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2169 (or 2166 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 18634518 is about 4316.7717104336. The cubic root of 18634518 is about 265.1181056553.

The spelling of 18634518 in words is "eighteen million, six hundred thirty-four thousand, five hundred eighteen".