18788406 has 48 divisors (see below), whose sum is σ = 46520064. Its totient is φ = 4953312.

The previous prime is 18788353. The next prime is 18788411. The reversal of 18788406 is 60488781.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5775 + ... + 8421.

It is an arithmetic number, because the mean of its divisors is an integer number (969168).

Almost surely, 2^18788406 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18788406, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23260032).

18788406 is an abundant number, since it is smaller than the sum of its proper divisors (27731658).

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

18788406 is a wasteful number, since it uses less digits than its factorization.

18788406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2685 (or 2672 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 42.

The square root of 18788406 is about 4334.5594931896. The cubic root of 18788406 is about 265.8459073224.

The spelling of 18788406 in words is "eighteen million, seven hundred eighty-eight thousand, four hundred six".