18105408 has 126 divisors (see below), whose sum is σ = 56256174. Its totient is φ = 5548032.

The previous prime is 18105403. The next prime is 18105413. The reversal of 18105408 is 80450181.

It is an interprime number because it is at equal distance from previous prime (18105403) and next prime (18105413).

It can be written as a sum of positive squares in only one way, i.e., 17040384 + 1065024 = 4128^2 + 1032^2 .

It is not an unprimeable number, because it can be changed into a prime (18105401) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 421035 + ... + 421077.

Almost surely, 2^18105408 is an apocalyptic number.

18105408 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18105408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28128087).

18105408 is an abundant number, since it is smaller than the sum of its proper divisors (38150766).

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

18105408 is a wasteful number, since it uses less digits than its factorization.

18105408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121 (or 65 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 27.

The square root of 18105408 is about 4255.0450056374. The cubic root of 18105408 is about 262.5847127950.

Adding to 18105408 its reverse (80450181), we get a palindrome (98555589).

It can be divided in two parts, 1 and 8105408, that added together give a square (8105409 = 2847²).

The spelling of 18105408 in words is "eighteen million, one hundred five thousand, four hundred eight".