1638168 has 64 divisors (see below), whose sum is σ = 4800000. Its totient is φ = 465696.

The previous prime is 1638167. The next prime is 1638191. The reversal of 1638168 is 8618361.

It is a nude number because it is divisible by every one of its digits.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1638167) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8133 + ... + 8331.

It is an arithmetic number, because the mean of its divisors is an integer number (75000).

2^1638168 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 1638168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2400000).

1638168 is an abundant number, since it is smaller than the sum of its proper divisors (3161832).

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

1638168 is a wasteful number, since it uses less digits than its factorization.

1638168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229 (or 211 counting only the distinct ones).

The product of its digits is 6912, while the sum is 33.

The square root of 1638168 is about 1279.9093717916. The cubic root of 1638168 is about 117.8834432713.

The spelling of 1638168 in words is "one million, six hundred thirty-eight thousand, one hundred sixty-eight".