2181648 has 80 divisors (see below), whose sum is σ = 6634496. Its totient is φ = 604800.

The previous prime is 2181629. The next prime is 2181649. The reversal of 2181648 is 8461812.

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

It is not an unprimeable number, because it can be changed into a prime (2181649) 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, 14373 + ... + 14523.

2^2181648 is an apocalyptic number.

2181648 is a gapful number since it is divisible by the number (28) 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 2181648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3317248).

2181648 is an abundant number, since it is smaller than the sum of its proper divisors (4452848).

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

2181648 is a wasteful number, since it uses less digits than its factorization.

2181648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212 (or 206 counting only the distinct ones).

The product of its digits is 3072, while the sum is 30.

The square root of 2181648 is about 1477.0402838108. The cubic root of 2181648 is about 129.6964911655.

Subtracting from 2181648 its product of digits (3072), we obtain a square (2178576 = 1476²).

The spelling of 2181648 in words is "two million, one hundred eighty-one thousand, six hundred forty-eight".