18405408 has 96 divisors (see below), whose sum is σ = 56246400. Its totient is φ = 5160960.

The previous prime is 18405397. The next prime is 18405421. The reversal of 18405408 is 80450481.

It is a tau number, because it is divible by the number of its divisors (96).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40768 + ... + 41216.

It is an arithmetic number, because the mean of its divisors is an integer number (585900).

Almost surely, 2^18405408 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18405408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28123200).

18405408 is an abundant number, since it is smaller than the sum of its proper divisors (37840992).

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

18405408 is a wasteful number, since it uses less digits than its factorization.

18405408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 530 (or 522 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 30.

The square root of 18405408 is about 4290.1524448439. The cubic root of 18405408 is about 264.0270862934.

Adding to 18405408 its reverse (80450481), we get a palindrome (98855889).

The spelling of 18405408 in words is "eighteen million, four hundred five thousand, four hundred eight".